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Sample records for active tumour targeting

  1. A review of the ligands and related targeting strategies for active targeting of paclitaxel to tumours.

    PubMed

    Li, Juan; Wang, Fengshan; Sun, Deqing; Wang, Rongmei

    2016-08-01

    It has been 30 years since the discovery of the anti-tumour property of paclitaxel (PTX), which has been successfully applied in clinic for the treatment of carcinomas of the lungs, breast and ovarian. However, PTX is poorly soluble in water and has no targeting and selectivity to tumour tissue. Recent advances in active tumour targeting of PTX delivery vehicles have addressed some of the issues related to lack of solubility in water and non-specific toxicities associated with PTX. These PTX delivery vehicles are designed for active targeting to specific cancer cells by the addition of ligands for recognition by specific receptors/antigens on cancer cells. This article will focus on various ligands and related targeting strategies serving as potential tools for active targeting of PTX to tumour tissues, illustrating their use in different tumour models. This review also highlights the need of further studies on the discovery of receptors in different cells of specific organ and ligands with binding efficiency to these specific receptors. PMID:26878228

  2. Hypoxia-mediated tumour targeting.

    PubMed

    Binley, K; Askham, Z; Martin, L; Spearman, H; Day, D; Kingsman, S; Naylor, S

    2003-04-01

    Hypoxia is a common physiological feature of tumours. It activates a signalling cascade that culminates in the stabilization of the HIF-1 transcription factor and activation of genes that possess a hypoxia response element (HRE). We have used an optimized hypoxia responsive promoter (OBHRE) to investigate hypoxia-targeted gene expression in vivo in the context of an adenovirus vector. The OBHRE promoter showed limited activity in the liver or spleen such that expression was 1000-fold lower than that driven by the strong CMV/IE promoter. However, in the context of the tumour microenvironment, the OBHRE promoter achieved expression levels comparable to that of the CMV/IE promoter. Next, we showed that an adenovirus expressing the human cytochrome P450 (CYP2B6) regulated by the OBHRE promoter delays tumour growth in response to the prodrug cyclophosphamide (CPA). Finally, we exploited the hepatotropism of adenovirus to investigate whether the OBHRE promoter could mitigate the hepatotoxicity of a recombinant adenovirus expressing thymidine kinase (TK) in the context of the prodrug ganciclovir (GCV). High-dose Ad.CMVTK/GCV treatment caused significant liver necrosis whereas the same dose of Ad.HRETK was well tolerated. These in vivo data demonstrate that hypoxia-targeted gene expression via the OBHRE promoter can be used to increase the therapeutic window of cytotoxic cancer gene therapy. PMID:12646859

  3. Aqueous synthesized near-infrared-emitting quantum dots for RGD-based in vivo active tumour targeting

    NASA Astrophysics Data System (ADS)

    Lu, Yimei; Zhong, Yiling; Wang, Jie; Su, Yuanyuan; Peng, Fei; Zhou, Yanfeng; Jiang, Xiangxu; He, Yao

    2013-04-01

    Over the past two decades, fluorescent quantum dots (QDs) have been highly attractive for a myriad of bioapplications due to their unique optical properties. For bioimaging applications, QD-based in vivo specific tumour targeting is vitally important in the biological and biomedical fields. Aqueous synthesized QDs (aqQDs) exhibit excellent aqueous dispersibility without requiring any post-treatment and have small hydrodynamic diameters (generally <5 nm), which are highly useful for bioimaging applications. We herein present the first example of in vivo active tumour targeting using water-dispersed near-infrared-emitting aqQDs modified with Arg-Gly-Asp (RGD) peptides. In vitro and in vivo studies (e.g., tumour cell labelling, histological analysis, and active tumour targeting) demonstrate that the prepared RGD-decorated aqQDs exhibit highly bio-specific properties, enabling sensitive and specific targeting of tumour sites in both cells and living animals. Our results suggest that the new class of RGD-decorated aqQDs are highly promising as fluorescent bioprobes for a wide range of biological applications.

  4. Aqueous synthesized near-infrared-emitting quantum dots for RGD-based in vivo active tumour targeting.

    PubMed

    Lu, Yimei; Zhong, Yiling; Wang, Jie; Su, Yuanyuan; Peng, Fei; Zhou, Yanfeng; Jiang, Xiangxu; He, Yao

    2013-04-01

    Over the past two decades, fluorescent quantum dots (QDs) have been highly attractive for a myriad of bioapplications due to their unique optical properties. For bioimaging applications, QD-based in vivo specific tumour targeting is vitally important in the biological and biomedical fields. Aqueous synthesized QDs (aqQDs) exhibit excellent aqueous dispersibility without requiring any post-treatment and have small hydrodynamic diameters (generally <5 nm), which are highly useful for bioimaging applications. We herein present the first example of in vivo active tumour targeting using water-dispersed near-infrared-emitting aqQDs modified with Arg-Gly-Asp (RGD) peptides. In vitro and in vivo studies (e.g., tumour cell labelling, histological analysis, and active tumour targeting) demonstrate that the prepared RGD-decorated aqQDs exhibit highly bio-specific properties, enabling sensitive and specific targeting of tumour sites in both cells and living animals. Our results suggest that the new class of RGD-decorated aqQDs are highly promising as fluorescent bioprobes for a wide range of biological applications. PMID:23478489

  5. Targeting FGFR2 with alofanib (RPT835) shows potent activity in tumour models.

    PubMed

    Tsimafeyeu, Ilya; Ludes-Meyers, John; Stepanova, Evgenia; Daeyaert, Frits; Kochenkov, Dmitry; Joose, Jean-Baptiste; Solomko, Eliso; Van Akene, Koen; Peretolchina, Nina; Yin, Wei; Ryabaya, Oxana; Byakhov, Mikhail; Tjulandin, Sergei

    2016-07-01

    Alofanib (RPT835) is a novel selective allosteric inhibitor of fibroblast growth factor receptor 2 (FGFR2). We showed previously that alofanib could bind to the extracellular domain of FGFR2 and has an inhibitory effect on FGF2-induced phoshphorylation of FRS2α. In the present study, we further showed that alofanib inhibited phosphorylation of FRS2α with the half maximal inhibitory concentration (IC50) values of 7 and 9 nmol/l in cancer cells expressing different FGFR2 isoforms. In a panel of four cell lines representing several tumour types (triple-negative breast cancer, melanoma, and ovarian cancer), alofanib inhibited FGF-mediated proliferation with 50% growth inhibition (GI50) values of 16-370 nmol/l. Alofanib dose dependently inhibited the proliferation and migration of human and mouse endothelial cells (GI50 11-58 nmol/l) compared with brivanib and bevacizumab. Treatment with alofanib ablated experimental FGF-induced angiogenesis in vivo. In a FGFR-driven human tumour xenograft model, oral administration of alofanib was well tolerated and resulted in potent antitumour activity. Importantly, alofanib was effective in FGFR2-expressing models. These results show that alofanib is a potent FGFR2 inhibitor and provide strong rationale for its evaluation in patients with FGFR2-driven cancers. PMID:27136102

  6. Tumour vasculature--a potential therapeutic target.

    PubMed Central

    Baillie, C. T.; Winslet, M. C.; Bradley, N. J.

    1995-01-01

    The tumour vasculature is vital for the establishment, growth and metastasis of solid tumours. Its physiological properties limit the effectiveness of conventional anti-cancer strategies. Therapeutic approaches directed at the tumour vasculature are reviewed, suggesting the potential of anti-angiogenesis and the targeting of vascular proliferation antigens as cancer treatments. PMID:7543770

  7. Isolation and functional characterization of chicken intestinal intra-epithelial lymphocytes showing natural killer cell activity against tumour target cells.

    PubMed Central

    Chai, J Y; Lillehoj, H S

    1988-01-01

    Intestinal intra-epithelial lymphocytes (IEL) of SC or FP chickens were isolated and examined for their natural killer (NK)-cell activity against chicken tumour cell lines, LSCC-RP9 (RP9), LSCC-RP12 (RP12), MDCC-MSB-1 (MSB-1) and MDCC-CU36 (CU36). In general, IEL of satisfactory yield and of good viability were obtained with EDTA treatment of the gut tissues, followed by rapid passages of the resultant cells through nylon-wool columns and centrifugation on two-step Percoll density gradients (45% and 80%). In 4-hr and 16-hr 51Cr-release assays, the NK-cell activity of chicken IEL depended not only upon the type of target cells but also upon the incubation time and the host genetic background. RP9, MSB-1 and CU36 were susceptible to NK lysis by IEL and by spleen cells, while RP12 was resistant to lysis even after a prolonged incubation. In kinetic studies the cytotoxicity was detactable from 2 hr after incubation and progressively increased up to 16 or 18 hr. The IEL of SC chickens revealed significantly higher levels of NK-cell activity against RP9 than FP-strain chickens, whereas their splenic NK-cell activity was not significantly different. Against MSB-1 targets, however, IEL of SC and FP chickens showed similar levels of NK-cell activity while their spleens did not (being higher in FP). When tested in FP chickens, IEL NK-cell activity was inhibited by the addition of unlabelled homologous target cells. In general, NK-cell activity was higher in the jejunum and ileum than in the duodenum and caecum. Efforts to enrich IEL NK-effector cells by discontinuous Percoll gradients were not successful. The results of the present study show that IEL of chicken intestine contain effector cells that can mediate NK-cell activity against chicken tumour cells. PMID:3338816

  8. Anti-tumour strategies aiming to target tumour-associated macrophages

    PubMed Central

    Tang, Xiaoqiang; Mo, Chunfen; Wang, Yongsheng; Wei, Dandan; Xiao, Hengyi

    2013-01-01

    Tumour-associated macrophages (TAMs) represent a predominant population of inflammatory cells that present in solid tumours. TAMs are mostly characterized as alternatively activated M2-like macrophages and are known to orchestrate nearly all stages of tumour progression. Experimental investigations indicate that TAMs contribute to drug-resistance and radio-protective effects, and clinical evidence shows that an elevated number of TAMs and their M2 profile are correlated with therapy failure and poor prognosis in cancer patients. Recently, many studies on TAM-targeted strategies have made significant progress and some pilot works have achieved encouraging results. Among these, connections between some anti-tumour drugs and their influence on TAMs have been suggested. In this review, we will summarize recent advances in TAM-targeted strategies for tumour therapy. Based on the proposed mechanisms, those strategies are grouped into four categories: (i) inhibiting macrophage recruitment; (ii) suppressing TAM survival; (iii) enhancing M1-like tumoricidal activity of TAMs; (iv) blocking M2-like tumour-promoting activity of TAMs. It is desired that further attention be drawn to this research field and more effort be made to promote TAM-targeted tumour therapy. PMID:23113570

  9. Targeted therapy of gastrointestinal stromal tumours

    PubMed Central

    Jakhetiya, Ashish; Garg, Pankaj Kumar; Prakash, Gaurav; Sharma, Jyoti; Pandey, Rambha; Pandey, Durgatosh

    2016-01-01

    Gastrointestinal stromal tumours (GISTs) are mesenchymal neoplasms originating in the gastrointestinal tract, usually in the stomach or the small intestine, and rarely elsewhere in the abdomen. The malignant potential of GISTs is variable ranging from small lesions with a benign behaviour to fatal sarcomas. The majority of the tumours stain positively for the CD-117 (KIT) and discovered on GIST-1 (DOG-1 or anoctamin 1) expression, and they are characterized by the presence of a driver kinase-activating mutation in either KIT or platelet-derived growth factor receptor α. Although surgery is the primary modality of treatment, almost half of the patients have disease recurrence following surgery, which highlights the need for an effective adjuvant therapy. Traditionally, GISTs are considered chemotherapy and radiotherapy resistant. With the advent of targeted therapy (tyrosine kinase inhibitors), there has been a paradigm shift in the management of GISTs in the last decade. We present a comprehensive review of targeted therapy in the management of GISTs. PMID:27231512

  10. Targeted therapy of gastrointestinal stromal tumours.

    PubMed

    Jakhetiya, Ashish; Garg, Pankaj Kumar; Prakash, Gaurav; Sharma, Jyoti; Pandey, Rambha; Pandey, Durgatosh

    2016-05-27

    Gastrointestinal stromal tumours (GISTs) are mesenchymal neoplasms originating in the gastrointestinal tract, usually in the stomach or the small intestine, and rarely elsewhere in the abdomen. The malignant potential of GISTs is variable ranging from small lesions with a benign behaviour to fatal sarcomas. The majority of the tumours stain positively for the CD-117 (KIT) and discovered on GIST-1 (DOG-1 or anoctamin 1) expression, and they are characterized by the presence of a driver kinase-activating mutation in either KIT or platelet-derived growth factor receptor α. Although surgery is the primary modality of treatment, almost half of the patients have disease recurrence following surgery, which highlights the need for an effective adjuvant therapy. Traditionally, GISTs are considered chemotherapy and radiotherapy resistant. With the advent of targeted therapy (tyrosine kinase inhibitors), there has been a paradigm shift in the management of GISTs in the last decade. We present a comprehensive review of targeted therapy in the management of GISTs. PMID:27231512

  11. Tumour macrophages as potential targets of bisphosphonates

    PubMed Central

    2011-01-01

    Tumour cells communicate with the cells of their microenvironment via a series of molecular and cellular interactions to aid their progression to a malignant state and ultimately their metastatic spread. Of the cells in the microenvironment with a key role in cancer development, tumour associated macrophages (TAMs) are among the most notable. Tumour cells release a range of chemokines, cytokines and growth factors to attract macrophages, and these in turn release numerous factors (e.g. VEGF, MMP-9 and EGF) that are implicated in invasion-promoting processes such as tumour cell growth, flicking of the angiogenic switch and immunosuppression. TAM density has been shown to correlate with poor prognosis in breast cancer, suggesting that these cells may represent a potential therapeutic target. However, there are currently no agents that specifically target TAM's available for clinical use. Bisphosphonates (BPs), such as zoledronic acid, are anti-resorptive agents approved for treatment of skeletal complication associated with metastatic breast cancer and prostate cancer. These agents act on osteoclasts, key cells in the bone microenvironment, to inhibit bone resorption. Over the past 30 years this has led to a great reduction in skeletal-related events (SRE's) in patients with advanced cancer and improved the morbidity associated with cancer-induced bone disease. However, there is now a growing body of evidence, both from in vitro and in vivo models, showing that zoledronic acid can also target tumour cells to increase apoptotic cell death and decrease proliferation, migration and invasion, and that this effect is significantly enhanced in combination with chemotherapy agents. Whether macrophages in the peripheral tumour microenvironment are exposed to sufficient levels of bisphosphonate to be affected is currently unknown. Macrophages belong to the same cell lineage as osteoclasts, the major target of BPs, and are highly phagocytic cells shown to be sensitive to

  12. Targeting ALCAM in the cryo-treated tumour microenvironment successfully induces systemic anti-tumour immunity.

    PubMed

    Kudo-Saito, Chie; Fuwa, Takafumi; Kawakami, Yutaka

    2016-07-01

    Cryoablative treatment has been widely used for treating cancer. However, the therapeutic efficacies are still controversial. The molecular mechanisms of the cryo-induced immune responses, particularly underlying the ineffectiveness, remain to be fully elucidated. In this study, we identified a new molecular mechanism involved in the cryo failure. We used cryo-ineffective metastatic tumour models that murine melanoma B16-F10 cells were subcutaneously and intravenously implanted into C57BL/6 mice. When the subcutaneous tumours were treated cryoablation on day 7 after tumour implantation, cells expressing activated leucocyte cell adhesion molecule (ALCAM/CD166) were significantly expanded not only locally in the treated tumours but also systemically in spleen and bone marrow of the mice. The cryo-induced ALCAM(+) cells including CD45(-) mesenchymal stem/stromal cells, CD11b(+)Gr1(+) myeloid-derived suppressor cells, and CD4(+)Foxp3(+) regulatory T cells significantly suppressed interferon γ production and cytotoxicity of tumour-specific CD8(+) T cells via ALCAM expressed in these cells. This suggests that systemic expansion of the ALCAM(+) cells negatively switches host-immune directivity to the tumour-supportive mode. Intratumoural injection with anti-ALCAM blocking monoclonal antibody (mAb) following the cryo treatment systemically induced tumour-specific CD8(+) T cells with higher cytotoxic activities, resulting in suppression of tumour growth and metastasis in the cryo-resistant tumour models. These suggest that expansion of ALCAM(+) cells is a determinant of limiting the cryo efficacy. Further combination with an immune checkpoint inhibitor anti-CTLA4 mAb optimized the anti-tumour efficacy of the dual-combination therapy. Targeting ALCAM may be a promising strategy for overcoming the cryo ineffectiveness leading to the better practical use of cryoablation in clinical treatment of cancer. PMID:27208904

  13. Nanoparticles that communicate in vivo to amplify tumour targeting

    NASA Astrophysics Data System (ADS)

    von Maltzahn, Geoffrey; Park, Ji-Ho; Lin, Kevin Y.; Singh, Neetu; Schwöppe, Christian; Mesters, Rolf; Berdel, Wolfgang E.; Ruoslahti, Erkki; Sailor, Michael J.; Bhatia, Sangeeta N.

    2011-07-01

    Nanomedicines have enormous potential to improve the precision of cancer therapy, yet our ability to efficiently home these materials to regions of disease in vivo remains very limited. Inspired by the ability of communication to improve targeting in biological systems, such as inflammatory-cell recruitment to sites of disease, we construct systems where synthetic biological and nanotechnological components communicate to amplify disease targeting in vivo. These systems are composed of ‘signalling’ modules (nanoparticles or engineered proteins) that target tumours and then locally activate the coagulation cascade to broadcast tumour location to clot-targeted ‘receiving’ nanoparticles in circulation that carry a diagnostic or therapeutic cargo, thereby amplifying their delivery. We show that communicating nanoparticle systems can be composed of multiple types of signalling and receiving modules, can transmit information through multiple molecular pathways in coagulation, can operate autonomously and can target over 40 times higher doses of chemotherapeutics to tumours than non-communicating controls.

  14. Targeting the tumour microenvironment in ovarian cancer.

    PubMed

    Hansen, Jean M; Coleman, Robert L; Sood, Anil K

    2016-03-01

    The study of cancer initiation, growth, and metastasis has traditionally been focused on cancer cells, and the view that they proliferate due to uncontrolled growth signalling owing to genetic derangements. However, uncontrolled growth in tumours cannot be explained solely by aberrations in cancer cells themselves. To fully understand the biological behaviour of tumours, it is essential to understand the microenvironment in which cancer cells exist, and how they manipulate the surrounding stroma to promote the malignant phenotype. Ovarian cancer is the leading cause of death from gynaecologic cancer worldwide. The majority of patients will have objective responses to standard tumour debulking surgery and platinum-taxane doublet chemotherapy, but most will experience disease recurrence and chemotherapy resistance. As such, a great deal of effort has been put forth to develop therapies that target the tumour microenvironment in ovarian cancer. Herein, we review the key components of the tumour microenvironment as they pertain to this disease, outline targeting opportunities and supporting evidence thus far, and discuss resistance to therapy. PMID:26849037

  15. Migrastatin analogues target fascin to block tumour metastasis

    SciTech Connect

    Chen, L.; Jakoncic, J.; Yang, S.; Zhang, J.; Huang, X.Y.

    2010-04-15

    Tumour metastasis is the primary cause of death of cancer patients. Development of new therapeutics preventing tumour metastasis is urgently needed. Migrastatin is a natural product secreted by Streptomyces, and synthesized migrastatin analogues such as macroketone are potent inhibitors of metastatic tumour cell migration, invasion and metastasis. Here we show that these migrastatin analogues target the actin-bundling protein fascin to inhibit its activity. X-ray crystal structural studies reveal that migrastatin analogues bind to one of the actin-binding sites on fascin. Our data demonstrate that actin cytoskeletal proteins such as fascin can be explored as new molecular targets for cancer treatment, in a similar manner to the microtubule protein tubulin.

  16. Oncolytic viruses & their specific targeting to tumour cells

    PubMed Central

    Singh, Prafull K.; Doley, Juwar; Kumar, G. Ravi; Sahoo, A.P.; Tiwari, Ashok K.

    2012-01-01

    Cancer is one of the major causes of death worldwide. In spite of achieving significant successes in medical sciences in the past few decades, the number of deaths due to cancer remains unchecked. The conventional chemotherapy and radiotherapy have limited therapeutic index and a plethora of treatment related side effects. This situation has provided an impetus for search of novel therapeutic strategies that can selectively destroy the tumour cells, leaving the normal cells unharmed. Viral oncotherapy is such a promising treatment modality that offers unique opportunity for tumour targeting. Numerous viruses with inherent anti-cancer activity have been identified and are in different phases of clinical trials. In the era of modern biotechnology and with better understanding of cancer biology and virology, it has become feasible to engineer the oncolytic viruses (OVs) to increase their tumour selectivity and enhance their oncolytic activity. In this review, the mechanisms by which oncolytic viruses kill the tumour cells have been discussed as also the development made in virotherapy for cancer treatment with emphasis on their tumour specific targeting. PMID:23168697

  17. Quantity and accessibility for specific targeting of receptors in tumours

    NASA Astrophysics Data System (ADS)

    Hussain, Sajid; Rodriguez-Fernandez, Maria; Braun, Gary B.; Doyle, Francis J.; Ruoslahti, Erkki

    2014-06-01

    Synaphic (ligand-directed) targeting of drugs is an important potential new approach to drug delivery, particularly in oncology. Considerable success with this approach has been achieved in the treatment of blood-borne cancers, but the advances with solid tumours have been modest. Here, we have studied the number and availability for ligand binding of the receptors for two targeting ligands. The results show that both paucity of total receptors and their poor availability are major bottlenecks in drug targeting. A tumour-penetrating peptide greatly increases the availability of receptors by promoting transport of the drug to the extravascular tumour tissue, but the number of available receptors still remains low, severely limiting the utility of the approach. Our results emphasize the importance of using drugs with high specific activity to avoid exceeding receptor capacity because any excess drug conjugate would lose the targeting advantage. The mathematical models we describe make it possible to focus on those aspects of the targeting mechanism that are most likely to have a substantial effect on the overall efficacy of the targeting.

  18. Targeting the erythropoietin receptor on glioma cells reduces tumour growth

    SciTech Connect

    Peres, Elodie A.; Valable, Samuel; Guillamo, Jean-Sebastien; Marteau, Lena; Bernaudin, Jean-Francois; Roussel, Simon; Lechapt-Zalcman, Emmanuele; Bernaudin, Myriam; Petit, Edwige

    2011-10-01

    Hypoxia has been shown to be one of the major events involved in EPO expression. Accordingly, EPO might be expressed by cerebral neoplastic cells, especially in glioblastoma, known to be highly hypoxic tumours. The expression of EPOR has been described in glioma cells. However, data from the literature remain descriptive and controversial. On the basis of an endogenous source of EPO in the brain, we have focused on a potential role of EPOR in brain tumour growth. In the present study, with complementary approaches to target EPO/EPOR signalling, we demonstrate the presence of a functional EPO/EPOR system on glioma cells leading to the activation of the ERK pathway. This EPO/EPOR system is involved in glioma cell proliferation in vitro. In vivo, we show that the down-regulation of EPOR expression on glioma cells reduces tumour growth and enhances animal survival. Our results support the hypothesis that EPOR signalling in tumour cells is involved in the control of glioma growth.

  19. Telomerase activity in 144 brain tumours.

    PubMed Central

    Sano, T.; Asai, A.; Mishima, K.; Fujimaki, T.; Kirino, T.

    1998-01-01

    Unlimited proliferation in immortalized cells is believed to be highly dependent on the activity of telomerase, a ribonucleoprotein that synthesizes telomeric repeats onto chromosome ends. Using a polymerase chain reaction-based telomeric repeat amplification protocol (TRAP) assay, we analysed telomerase activity in 99 benign and 45 malignant brain tumours. The TRAP assay results were quantitated by normalizing the telomerase activity of each specimen to that of human glioma cell line T98G to obtain the relative telomerase activity. Telomerase activity was also assessed visually from the autoradiograms as being positive or negative. One hundred and sixteen tumours with negative telomerase activity had null relative telomerase activity, whereas 28 tumours with positive telomerase activity had relative telomerase activities of 12-84.3% (mean 0% vs 36.1 +/- 19.3%, P < 0.0001). Thus, quantification of telomerase activity confirmed the results of the visual evaluation of telomerase activity on autoradiograms. Based on the assessment, malignant brain tumours had a higher positive rate of telomerase activity than benign tumours (57.8% vs 2.0%, P < 0.001). These data indicate that positive telomerase activity is strongly associated with malignant brain tumours and is rather rare in benign tumours, such as neurinomas or meningiomas. Images Figure 2 PMID:9635839

  20. Translational aspects in targeting the stromal tumour microenvironment: from bench to bedside

    PubMed Central

    Bhome, R; Al Saihati, HA; Goh, RW; Bullock, MD; Primrose, JN; Thomas, GJ; Sayan, AE; Mirnezami, AH

    2016-01-01

    Solid tumours comprise, not only malignant cells but also a variety of stromal cells and extracellular matrix proteins. These components interact via an array of signalling pathways to create an adaptable network that may act to promote or suppress cancer progression. To date, the majority of anti-tumour chemotherapeutic agents have principally sought to target the cancer cell. Consequently, resistance develops because of clonal evolution, as a result of selection pressure during tumour expansion. The concept of activating or inhibiting other cell types within the tumour microenvironment is relatively novel and has the advantage of targeting cells which are genetically stable and less likely to develop resistance. This review outlines key players in the stromal tumour microenvironment and discusses potential targeting strategies that may offer therapeutic benefit. PMID:27275004

  1. Engineered affinity proteins for tumour-targeting applications.

    PubMed

    Friedman, Mikaela; Ståhl, Stefan

    2009-05-01

    Targeting of tumour-associated antigens is an expanding treatment modality in clinical oncology as an alternative to, or in combination with, conventional treatments, such as chemotherapy, external-radiation therapy and surgery. Targeting of antigens that are unique or more highly expressed in tumours than in normal tissues can be used to increase the specificity and reduce the cytotoxic effect on normal tissues. Several targeting agents have been studied for clinical use, where monoclonal antibodies have been the ones most widely used. More than 20 monoclonal antibodies are approved for therapy today and the largest field is oncology. Advances in genetic engineering and in vitro selection technology has enabled the feasible high-throughput generation of monoclonal antibodies, antibody derivatives [e.g. scFvs, Fab molecules, dAbs (single-domain antibodies), diabodies and minibodies] and more recently also non-immunoglobulin scaffold proteins. Several of these affinity proteins have been investigated for both in vivo diagnostics and therapy. Affinity proteins in tumour-targeted therapy can affect tumour progression by altering signal transduction or by delivering a payload of toxin, drug or radionuclide. The ErbB receptor family has been extensively studied as biomarkers in tumour targeting, primarily for therapy using monoclonal antibodies. Two receptors in the ErbB family, EGFR (epidermal growth factor receptor) and HER2 (epidermal growth factor receptor 2), are overexpressed in various malignancies and associated with poor patient prognosis and are therefore interesting targets for solid tumours. In the present review, strategies are described for tumour targeting of solid tumours using affinity proteins to deliver radionuclides, either for molecular imaging or radiotherapy. Antibodies, antibody derivatives and non-immunoglobulin scaffold proteins are discussed with a certain focus on the affibody (Affibody) molecule. PMID:19341363

  2. New approaches to targeted drug delivery to tumour cells

    NASA Astrophysics Data System (ADS)

    Severin, E. S.

    2015-01-01

    Basic approaches to the design of targeted drugs for the treatment of human malignant tumours have been considered. The stages of the development of these approaches have been described in detail and theoretically substantiated, and basic experimental results have been reported. Considerable attention is paid to the general characteristic of nanopharmacological drugs and to the description of mechanisms of cellular interactions with nanodrugs. The potentialities and limitations of application of nanodrugs for cancer therapy and treatment of other diseases have been considered. The use of nanodrugs conjugated with vector molecules seems to be the most promising trend of targeted therapy of malignant tumours. The bibliography includes 122 references.

  3. Mitochondria: An intriguing target for killing tumour-initiating cells.

    PubMed

    Yan, Bing; Dong, Lanfeng; Neuzil, Jiri

    2016-01-01

    Tumour-initiating cells (TICs) play a pivotal role in cancer initiation, metastasis and recurrence, as well as in resistance to therapy. Therefore, development of drugs targeting TICs has become a focus of contemporary research. Mitochondria have emerged as a promising target of anti-cancer therapies due to their specific role in cancer metabolism and modulation of apoptotic pathways. Mitochondria of TICs possess special characteristics, some of which can be utilised to design drugs specifically targeting these cells. In this paper, we will review recent research on TICs and their mitochondria, and introduce drugs that kill these cells by way of mitochondrial targeting. PMID:26702582

  4. MPLA incorporation into DC-targeting glycoliposomes favours anti-tumour T cell responses.

    PubMed

    Boks, Martine A; Ambrosini, Martino; Bruijns, Sven C; Kalay, Hakan; van Bloois, Louis; Storm, Gert; Garcia-Vallejo, Juan J; van Kooyk, Yvette

    2015-10-28

    Dendritic cells (DC) are attractive targets for cancer immunotherapy as they initiate strong and long-lived tumour-specific T cell responses. DC can be effectively targeted in vivo with tumour antigens by using nanocarriers such as liposomes. Cross-presentation of tumour antigens is enhanced with strong adjuvants such as TLR ligands. However, often these adjuvants have off-target effects, and would benefit from a DC-specific targeting strategy, similar to the tumour antigen. The goal of this study was to develop a strategy for specifically targeting DC with tumour antigen and adjuvant by using glycoliposomes. We have generated liposomes containing the glycan Lewis(Le)(X) which is highly specific for the C-type lectin receptor DC-SIGN expressed by DC. Le(X)-modified liposomes were taken up by human monocyte-derived DC in a DC-SIGN-specific manner. As adjuvants we incorporated the TLR ligands Pam3CySK4, Poly I:C, MPLA and R848 into liposomes and compared their adjuvant capacity on DC. Incorporation of the TLR4 ligand MPLA into glycoliposomes induced DC maturation and production of pro-inflammatory cytokines, in a DC-SIGN-specific manner, and DC activation was comparable to administration of soluble MPLA. Incorporation of MPLA into glycoliposomes significantly enhanced antigen cross-presentation of the melanoma tumour antigen gp100280-288 peptide to CD8(+) T cells compared to non-glycosylated MPLA liposomes. Importantly, antigen cross-presentation of the gp100280-288 peptide was significantly higher using MPLA glycoliposomes compared to the co-administration of soluble MPLA with glycoliposomes. Taken together, our data demonstrates that specific targeting of a gp100 tumour antigen and the adjuvant MPLA to DC-SIGN-expressing DC enhances the uptake of peptide-containing liposomes, the activation of DC, and induces tumour antigen-specific CD8(+) T cell responses. These data demonstrate that adjuvant-containing glycoliposome-based vaccines targeting DC-SIGN(+) DC

  5. Tumour promoter activity in Malaysian Euphorbiaceae.

    PubMed Central

    Norhanom, A. W.; Yadav, M.

    1995-01-01

    Herbal medication has been practised by the rural Malaysian Malays for a long time. However, the long-term side-effects have never been studied. In the present study, 48 species of Euphorbiaceae were screened for tumour-promoter activity by means of an in vitro assay using a human lymphoblastoid cell line harbouring the Epstein-Barr virus (EBV) genome. Twenty-seven per cent (13 out of 48) of the species tested were found to be positive, and in four species, namely Breynia coronata Hk.f, Codiaeum variegatum (L) Bl, Euphorbia atoto and Exocoecaria agallocha, EBV-inducing activity was observed when the plant extracts were tested at low concentrations of between 0.2 and 1.2 micrograms ml-1 in cell culture. This observation warrants attention from the regular users of these plants because regular use of plants with tumour-promoting activity could well be an aetiological factor for the promotion of tumours among rural Malaysian Malays. PMID:7710943

  6. Magnetoferritin nanoparticles for targeting and visualizing tumour tissues

    NASA Astrophysics Data System (ADS)

    Fan, Kelong; Cao, Changqian; Pan, Yongxin; Lu, Di; Yang, Dongling; Feng, Jing; Song, Lina; Liang, Minmin; Yan, Xiyun

    2012-07-01

    Engineered nanoparticles have been used to provide diagnostic, therapeutic and prognostic information about the status of disease. Nanoparticles developed for these purposes are typically modified with targeting ligands (such as antibodies, peptides or small molecules) or contrast agents using complicated processes and expensive reagents. Moreover, this approach can lead to an excess of ligands on the nanoparticle surface, and this causes non-specific binding and aggregation of nanoparticles, which decreases detection sensitivity. Here, we show that magnetoferritin nanoparticles (M-HFn) can be used to target and visualize tumour tissues without the use of any targeting ligands or contrast agents. Iron oxide nanoparticles are encapsulated inside a recombinant human heavy-chain ferritin (HFn) protein shell, which binds to tumour cells that overexpress transferrin receptor 1 (TfR1). The iron oxide core catalyses the oxidation of peroxidase substrates in the presence of hydrogen peroxide to produce a colour reaction that is used to visualize tumour tissues. We examined 474 clinical specimens from patients with nine types of cancer and verified that these nanoparticles can distinguish cancerous cells from normal cells with a sensitivity of 98% and specificity of 95%.

  7. Bone morphogenetic protein signalling activity distinguishes histological subsets of paediatric germ cell tumours.

    PubMed

    Fustino, N; Rakheja, D; Ateek, C S; Neumann, J C; Amatruda, J F

    2011-08-01

    Germ cell tumours (GCTs) are cancers of the testis, ovary or extragonadal sites that occur in infants, children and adults. Testicular GCT is the most common cancer in young men aged 15-40 years. Abnormalities in developmental signalling pathways such as wnt/β-catenin, TGF-β/BMP and Hedgehog have been described in many childhood tumours. To date, however, the status of BMP signalling in GCTs has not been described. Herein, we examine BMP-SMAD signalling in a set of clinically-annotated paediatric GCTs. We find that BMP signalling activity is absent in undifferentiated tumours such as seminomas and dysgerminomas, but robustly present in most yolk sac tumours, a differentiated tumour type. Gene expression profiling of TGF-β/BMP pathway genes in germinomas and yolk sac tumours reveals a set of genes that distinguish the two tumour types. There is significant intertumoural heterogeneity between tumours of the same histological subclass, implying that the BMP pathway can be differentially regulated in individual tumours. Finally, through miRNA expression profiling, we identify differential regulation of a set of miRNAs predicted to target the TGF-β/BMP pathway at multiple sites. Taken together, these results suggest that the BMP signalling pathway may represent a new therapeutical target for childhood GCTs. PMID:21696393

  8. Targeted Therapies for Advanced Ewing Sarcoma Family of Tumours

    PubMed Central

    Jiang, Yunyun; Ludwig, Joseph; Janku, Filip

    2015-01-01

    The prognosis of adolescent and young adult patients battling metastatic Ewing Sarcoma Family of Tumours (ESFT) remains less than 30% despite the development of systemic therapies. In the era of personalized medicine, novel molecular targets have been tested in preclinical or clinical settings in ESFT. In this review, we focus on early clinical and translational research that identified multiple molecular targets, including IGF-1R; mTOR; tyrosine kinase inhibitors; EWS-FLI1-related targets, and others. Overall, novel targeted therapies demonstrated modest efficacy; however pronounced and durable antineoplastic responses have been observed in small subsets of treated patients, for example with IGF-1R antibodies. Identifying outcome-predicting biomarkers and overcoming treatment resistance remain major challenges. Due to the rarity of ESFT, multi-institutional collaboration efforts of clinicians, basic and translational scientists are needed in order to understand biology of therapeutic response or resistance, which can lead to development of novel therapeutic methods and improved patient outcomes. PMID:25869102

  9. ELL targets c-Myc for proteasomal degradation and suppresses tumour growth

    PubMed Central

    Chen, Yu; Zhou, Chi; Ji, Wei; Mei, Zhichao; Hu, Bo; Zhang, Wei; Zhang, Dawei; Wang, Jing; Liu, Xing; Ouyang, Gang; Zhou, Jiangang; Xiao, Wuhan

    2016-01-01

    Increasing evidence supports that ELL (eleven–nineteen lysine-rich leukaemia) is a key regulator of transcriptional elongation, but the physiological function of Ell in mammals remains elusive. Here we show that ELL functions as an E3 ubiquitin ligase and targets c-Myc for proteasomal degradation. In addition, we identify that UbcH8 serves as a ubiquitin-conjugating enzyme in this pathway. Cysteine 595 of ELL is an active site of the enzyme; its mutation to alanine (C595A) renders the protein unable to promote the ubiquitination and degradation of c-Myc. ELL-mediated c-Myc degradation inhibits c-Myc-dependent transcriptional activity and cell proliferation, and also suppresses c-Myc-dependent xenograft tumour growth. In contrast, the ELL(C595A) mutant not only loses the ability to inhibit cell proliferation and xenograft tumour growth, but also promotes tumour metastasis. Thus, our work reveals a previously unrecognized function for ELL as an E3 ubiquitin ligase for c-Myc and a potential tumour suppressor. PMID:27009366

  10. Isolated limb perfusion with melphalan, tumour necrosis factor-alpha and oncolytic vaccinia virus improves tumour targeting and prolongs survival in a rat model of advanced extremity sarcoma.

    PubMed

    Pencavel, Tim D; Wilkinson, Michelle J; Mansfield, David C; Khan, Aadil A; Seth, Rohit; Karapanagiotou, Eleni M; Roulstone, Victoria; Aguilar, Richard J; Chen, Nanhai G; Szalay, Aladar A; Hayes, Andrew J; Harrington, Kevin J

    2015-02-15

    Isolated limb perfusion (ILP) is a treatment for advanced extremity sarcoma and in-transit melanoma. Advancing this procedure by investigating the addition of novel agents, such as cancer-selective oncolytic viruses, may improve both the therapeutic efficacy of ILP and the tumour-targeted delivery of oncolytic virotherapy. Standard in vitro assays were used to characterise single agent and combinatorial activities of melphalan, tumour necrosis factor-alpha (TNF-α) and Lister strain vaccinia virus (GLV-1h68) against BN175 rat sarcoma cells. An orthotopic model of advanced extremity sarcoma was used to evaluate survival of animals after ILP with combinations of TNF-α, melphalan and GLV-1h68. We investigated the efficiency of viral tumour delivery by ILP compared to intravenous therapy, the locoregional and systemic biodistribution of virus after ILP, and the effect of mode of administration on antibody response. The combination of melphalan and GLV-1h68 was synergistic in vitro. The addition of virus to standard ILP regimens was well tolerated and demonstrated superior tumour targeting compared to intravenous administration. Triple therapy (melphalan/TNF-α/GLV-1h68) resulted in increased tumour growth delay and enhanced survival compared to other treatment regimens. Live virus was recovered in large amounts from perfused regions, but in smaller amounts from systemic organs. The addition of oncolytic vaccinia virus to existing TNF-α/melphalan-based ILP strategies results in survival advantage in an immunocompetent rat model of advanced extremity sarcoma. Virus administered by ILP has superior tumour targeting compared to intravenous delivery. Further evaluation and clinical translation of this approach is warranted. PMID:24978211

  11. Tumour cell-derived Wnt7a recruits and activates fibroblasts to promote tumour aggressiveness

    PubMed Central

    Avgustinova, Alexandra; Iravani, Marjan; Robertson, David; Fearns, Antony; Gao, Qiong; Klingbeil, Pamela; Hanby, Andrew M.; Speirs, Valerie; Sahai, Erik; Calvo, Fernando; Isacke, Clare M.

    2016-01-01

    Stromal fibroblast recruitment to tumours and activation to a cancer-associated fibroblast (CAF) phenotype has been implicated in promoting primary tumour growth and progression to metastatic disease. However, the mechanisms underlying the tumour:fibroblast crosstalk that drive the intertumoural stromal heterogeneity remain poorly understood. Using in vivo models we identify Wnt7a as a key factor secreted exclusively by aggressive breast tumour cells, which induces CAF conversion. Functionally, this results in extracellular matrix remodelling to create a permissive environment for tumour cell invasion and promotion of distant metastasis. Mechanistically, Wnt7a-mediated fibroblast activation is not dependent on classical Wnt signalling. Instead, we demonstrate that Wnt7a potentiates TGFβ receptor signalling both in 3D in vitro and in vivo models, thus highlighting the interaction between two of the key signalling pathways in development and disease. Importantly, in clinical breast cancer cohorts, tumour cell Wnt7a expression correlates with a desmoplastic, poor-prognosis stroma and poor patient outcome. PMID:26777421

  12. miR-135b inhibits tumour metastasis in prostate cancer by targeting STAT6

    PubMed Central

    WANG, NING; TAO, LIANGJUN; ZHONG, HUAN; ZHAO, SIHAI; YU, YING; YU, BIN; CHEN, XIAONONG; GAO, JIANGUO; WANG, RONGJIANG

    2016-01-01

    MicroRNAs (miRNAs) are small non-coding RNAs that participate in several cellular functions and tumour progression. A previous microarray study demonstrated that miR-135b is downregulated in prostate cancer (PCa) cells, but the role and molecular mechanism of miR-135b in the regulation of tumour metastasis remain to be elucidated. In the present study, significant downregulation of miR-135b in PCa tissues, compared with noncancerous tissues, was detected by reverse transcription-quantitative polymerase chain reaction. Furthermore, the expression of miR-135b was demonstrated to be associated with the pathological stage and the levels of total and free prostate-specific antigen (PSA) in PCa cells. In addition, signal transducer and activator of transcription 6 (STAT6) was identified as a target of miR-135b in PCa cells by luciferase activity and western blot assays. The upregulation of miR-135b in PCa cells led to reduced expression of STAT6 in the cytoplasm and nucleus of these cells, while the overexpression of miR-135b and knockdown of STAT6 were able to inhibit the migration and invasion abilities of PCa cells in vitro. Therefore, the results of the present study indicate that miR-135b suppresses tumour metastasis by targeting STAT6. PMID:26870245

  13. Endogenous pacemaker activity of rat tumour somatotrophs

    PubMed Central

    Kwiecien, Renata; Robert, Christophe; Cannon, Robert; Vigues, Stephan; Arnoux, Annie; Kordon, Claude; Hammond, Constance

    1998-01-01

    Cells derived from a rat pituitary tumour (GC cell line) that continuously release growth hormone behave as endogenous pacemakers. In simultaneous patch clamp recordings and cytosolic Ca2+ concentration ([Ca2+]i) imaging, they displayed rhythmic action potentials (44.7 ± 2.7 mV, 178 ± 40 ms, 0.30 ± 0.04 Hz) and concomitant [Ca2+]i transients (374 ± 57 nM, 1.0 ± 0.2 s, 0.27 ± 0.03 Hz). Action potentials and [Ca2+]i transients were reversibly blocked by removal of external Ca2+, addition of nifedipine (1 μM) or Ni2+ (40 μM), but were insensitive to TTX (1 μM). An L-type Ca2+ current activated at -33.6 ± 0.4 mV (holding potential (Vh), −40 mV), peaked at -1.8 ± 1.3 mV, was reduced by nifedipine and enhanced by S-(+)-SDZ 202 791. A T/R-type Ca2+ current activated at -41.7 ± 2.7 mV (Vh, -80 or -60 mV), peaked at -9.2 ± 3.0 mV, was reduced by low concentrations of Ni2+ (40 μM) or Cd2+ (10 μM) and was toxin resistant. Parallel experiments revealed the expression of the class E calcium channel α1-subunit mRNA. The K+ channel blockers TEA (25 mM) and charybdotoxin (10–100 nM) enhanced spike amplitude and/or duration. Apamin (100 nM) also strongly reduced the after-spike hyperpolarization. The outward K+ tail current evoked by a depolarizing step that mimicked an action potential reversed at −69.8 ± 0.3 mV, presented two components, lasted 2–3 s and was totally blocked by Cd2+ (400 μM). The slow pacemaker depolarization (3.5 ± 0.4 s) that separated consecutive spikes corresponded to a 2- to 3-fold increase in membrane resistance, was strongly Na+ sensitive but TTX insensitive. Computer simulations showed that pacemaker activity can be reproduced by a minimum of six currents: an L-type Ca2+ current underlies the rising phase of action potentials that are repolarized by a delayed rectifier and Ca2+-activated K+ currents. In between spikes, the decay of Ca2+-activated K+ currents and a persistent inward cationic current depolarize the membrane

  14. Self-assembly of carbon nanotubes and antibodies on tumours for targeted, amplified delivery

    PubMed Central

    Mulvey, J. Justin; Villa, Carlos H.; McDevitt, Michael R.; Escorcia, Freddy E.; Casey, Emily; Scheinberg, David A.

    2013-01-01

    Single-walled carbon nanotubes (SWNTs) can deliver imaging agents or drugs to tumours and offer significant advantages over approaches based on antibodies or other nanomaterials. In particular, the nanotubes can carry a substantial amount of cargo (100 times more than a monoclonal antibody), but can still be rapidly eliminated from circulation by renal filtration, like a small molecule, due to their high aspect ratio. Here we show that SWNTs can target tumours in a two-step approach in which nanotubes modified with morpholino oligonucleotide sequences bind to cancer cells that have been pre-targeted with antibodies modified with oligonucleotide strands complementary to those on the nanotubes. The nanotubes can carry fluorophores or radioisotopes, and were shown to selectively bind to cancer cells in vitro and in tumour-bearing xenografted mice. The binding process is also found to lead to antigen capping and internalization of the antibody/nanotube complexes. The nanotube conjugates were labelled with both alpha-particle and gamma-ray emitting isotopes, at high specific activities. Conjugates labelled with alpha-particle generating 225Ac were found to clear rapidly, thus mitigating radioisotope toxicity, and were shown to be therapeutically effective in vivo. PMID:24077028

  15. Targeting Human Gastrointestinal Stromal Tumour Cells with a Quadruplex-binding Small Molecule

    PubMed Central

    Gunaratnam, Mekala; Beltran, Monica; Galesa, Katja; Haider, Shozeb M.; Reszka, Anthony P.; Cuenca, Francisco; Fletcher, Jonathan A.; Neidle, Stephen

    2010-01-01

    The majority of human gastrointestinal stromal tumours (GIST) are driven by activating mutations in the proto-oncogene KIT, a tyrosine kinase receptor. Clinical treatment with imatinib targets the kinase domain of KIT, but tumour regrowth occurs as a result of the development of resistant mutations in the kinase active site. An alternative small-molecule approach to GIST therapy is described, in which the KIT gene is directly targeted, and thus kinase resistance may be circumvented. A naphthalene dimiide derivative has been used to demonstrate the concept of dual quadruplex targeting. This compound strongly stabilises both telomeric quadruplex DNA and quadruplex sites in the KIT promoter in vitro. It is shown here that the compound is a potent inducer of growth arrest in a patient-derived GIST cell line at a concentration (ca 1μM) that also results in effective inhibition of telomerase activity and almost complete suppression of KIT mRNA and KIT protein expression. Molecular modelling studies with a telomeric quadruplex have been used to rationalise aspects of the experimental quadruplex melting data. PMID:19469547

  16. Self-assembly of carbon nanotubes and antibodies on tumours for targeted amplified delivery

    NASA Astrophysics Data System (ADS)

    Mulvey, J. Justin; Villa, Carlos H.; McDevitt, Michael R.; Escorcia, Freddy E.; Casey, Emily; Scheinberg, David A.

    2013-10-01

    Single-walled carbon nanotubes (SWNTs) can deliver imaging agents or drugs to tumours and offer significant advantages over approaches based on antibodies or other nanomaterials. In particular, the nanotubes can carry a substantial amount of cargo (100 times more than a monoclonal antibody), but can still be rapidly eliminated from the circulation by renal filtration, like a small molecule, due to their high aspect ratio. Here we show that SWNTs can target tumours in a two-step approach in which nanotubes modified with morpholino oligonucleotide sequences bind to cancer cells that have been pretargeted with antibodies modified with oligonucleotide strands complementary to those on the nanotubes. The nanotubes can carry fluorophores or radioisotopes, and are shown to selectively bind to cancer cells in vitro and in tumour-bearing xenografted mice. The binding process is also found to lead to antigen capping and internalization of the antibody-nanotube complexes. The nanotube conjugates were labelled with both alpha-particle and gamma-ray emitting isotopes, at high specific activities. Conjugates labelled with alpha-particle-generating 225Ac were found to clear rapidly, thus mitigating radioisotope toxicity, and were shown to be therapeutically effective in vivo.

  17. Re-programming tumour cell metabolism to treat cancer: no lone target for lonidamine.

    PubMed

    Bhutia, Yangzom D; Babu, Ellappan; Ganapathy, Vadivel

    2016-06-01

    Tumour cell metabolism is very different from normal cell metabolism; cancer cells re-programme the metabolic pathways that occur in normal cells in such a manner that it optimizes their proliferation, growth and survival. Although this metabolic re-programming obviously operates to the advantage of the tumour, it also offers unique opportunities for effective cancer therapy. Molecules that target the tumour cell-specific metabolic pathways have potential as novel anti-cancer drugs. Lonidamine belongs to this group of molecules and is already in use in some countries for cancer treatment. It has been known for a long time that lonidamine interferes with energy production in tumour cells by inhibiting hexokinase II (HKII), a glycolytic enzyme. However, subsequent studies have uncovered additional pharmacological targets for the drug, which include the electron transport chain and the mitochondrial permeability transition pore, thus expanding the pharmacological effects of the drug on tumour cell metabolism. A study by Nancolas et al. in a recent issue of the Biochemical Journal identifies two additional new targets for lonidamine: the pyruvate transporter in the mitochondria and the H(+)-coupled monocarboxylate transporters in the plasma membrane (PM). It is thus becoming increasingly apparent that the anti-cancer effects of lonidamine do not occur through a single target; the drug works at multiple sites. Irrespective of the molecular targets, what lonidamine does in the end is to undo what the tumour cells have done in terms of re-programming cellular metabolism and mitochondrial function. PMID:27234586

  18. Re-programming tumour cell metabolism to treat cancer: no lone target for lonidamine

    PubMed Central

    Bhutia, Yangzom D.; Babu, Ellappan; Ganapathy, Vadivel

    2016-01-01

    Tumour cell metabolism is very different from normal cell metabolism; cancer cells re-programme the metabolic pathways that occur in normal cells in such a manner that it optimizes their proliferation, growth and survival. Although this metabolic re-programming obviously operates to the advantage of the tumour, it also offers unique opportunities for effective cancer therapy. Molecules that target the tumour cell-specific metabolic pathways have potential as novel anti-cancer drugs. Lonidamine belongs to this group of molecules and is already in use in some countries for cancer treatment. It has been known for a long time that lonidamine interferes with energy production in tumour cells by inhibiting hexokinase II (HKII), a glycolytic enzyme. However, subsequent studies have uncovered additional pharmacological targets for the drug, which include the electron transport chain and the mitochondrial permeability transition pore, thus expanding the pharmacological effects of the drug on tumour cell metabolism. A study by Nancolas et al. in a recent issue of the Biochemical Journal identifies two additional new targets for lonidamine: the pyruvate transporter in the mitochondria and the H+-coupled monocarboxylate transporters in the plasma membrane (PM). It is thus becoming increasingly apparent that the anti-cancer effects of lonidamine do not occur through a single target; the drug works at multiple sites. Irrespective of the molecular targets, what lonidamine does in the end is to undo what the tumour cells have done in terms of re-programming cellular metabolism and mitochondrial function. PMID:27234586

  19. Size Matters: Developing Design Rules to Engineer Nanoparticles for Solid Tumour Targeting

    NASA Astrophysics Data System (ADS)

    Sykes, Edward Alexander

    Nanotechnology enables the design of highly customizable platforms for producing minimally invasive and programmable strategies for cancer diagnosis and treatment. Advances in this field have demonstrated that nanoparticles can enhance specificity of anti-cancer agents, respond to tumour-specific cues, and direct the visualization of biological targets in vivo. . Nanoparticles can be synthesized within the 1 to 100 nm range to achieve different electromagnetic properties and specifically interact with biological tissues by tuning their size, shape, and surface chemistry. However, it remains unclear which physicochemical parameters are critical for delivering nanomaterials to the tumour site. With less than 5% of administered nanoparticles reaching the tumour, engineering of nanoparticles for effective delivery to solid tumours remains a critical challenge to cancer nanomedicine. A more comprehensive understanding of the interplay between the nanomaterial physicochemical properties and biological systems is necessary to enhance the efficacy of nanoparticle tumour targeting. This thesis explores how nanoparticle size and functionalization with cancer cell specific agents impact nanoparticle delivery to tumours. Furthermore, this doctoral work (i) discusses how tumour structure evolves with growth, (ii) elucidates how such changes modulate nanoparticle accumulation, and (iii) identifies how the skin serves as a significant off-target site for nanoparticle uptake. This thesis also demonstrates the utility of empirically-derived parametric models, Monte Carlo simulations, and decision matrices for mechanistically understanding and predicting the impact of nanomaterial features and tumour biology on nanoparticle fate in vivo. These topics establish key design considerations to tailor nanoparticles for enhanced tumour targeting. Collectively, the concepts presented herein form a fundamental framework for the development of personalized nanomedicine and nano

  20. Anti-tumour activity of oncolytic Western Reserve vaccinia viruses in canine tumour cell lines, xenografts, and fresh tumour biopsies.

    PubMed

    Autio, K; Knuuttila, A; Kipar, A; Ahonen, M; Parviainen, S; Diaconu, I; Kanerva, A; Hakonen, T; Vähä-Koskela, M; Hemminki, A

    2014-10-10

    Cancer is one of the most common reasons for death in dogs. One promising approach is oncolytic virotherapy. We assessed the oncolytic effect of genetically modified vaccinia viruses in canine cancer cells, in freshly excised tumour biopsies, and in mice harbouring canine tumour xenografts. Tumour transduction efficacy was assessed using virus expressing luciferase or fluorescent marker genes and oncolysis was quantified by a colorimetric cell viability assay. Oncolytic efficacy in vivo was evaluated in a nude mouse xenograft model. Vaccinia virus was shown to infect most tested canine cancer cell lines and primary surgical tumour tissues. Virus infection significantly reduced tumour growth in the xenograft model. Oncolytic vaccinia virus has antitumour effects against canine cancer cells and experimental tumours and is able to replicate in freshly excised patient tumour tissue. Our results suggest that oncolytic vaccinia virus may offer an effective treatment option for otherwise incurable canine tumours. PMID:25302859

  1. Activation and activities of the p53 tumour suppressor protein

    PubMed Central

    Bálint, É; Vousden, K H

    2001-01-01

    The p53 tumour suppressor protein inhibits malignant progression by mediating cell cycle arrest, apoptosis or repair following cellular stress. One of the major regulators of p53 function is the MDM2 protein, and multiple forms of cellular stress activate p53 by inhibiting the MDM2-mediated degradation of p53. Mutations in p53, or disruption of the pathways that allow activation of p53, seem to be a general feature of all cancers. Here we review recent advances in our understanding of the pathways that regulate p53 and the pathways that are induced by p53, as well as their implications for cancer therapy. © 2001 Cancer Research Campaign http://www.bjcancer.com PMID:11747320

  2. SARI inhibits angiogenesis and tumour growth of human colon cancer through directly targeting ceruloplasmin.

    PubMed

    Dai, Lei; Cui, Xueliang; Zhang, Xin; Cheng, Lin; Liu, Yi; Yang, Yang; Fan, Ping; Wang, Qingnan; Lin, Yi; Zhang, Junfeng; Li, Chunlei; Mao, Ying; Wang, Qin; Su, Xiaolan; Zhang, Shuang; Peng, Yong; Yang, Hanshuo; Hu, Xun; Yang, Jinliang; Huang, Meijuan; Xiang, Rong; Yu, Dechao; Zhou, Zongguang; Wei, Yuquan; Deng, Hongxin

    2016-01-01

    SARI, also called as BATF2, belongs to the BATF family and has been implicated in cancer cell growth inhibition. However, the role and mechanism of SARI in tumour angiogenesis are elusive. Here we demonstrate that SARI deficiency facilitates AOM/DSS-induced colonic tumorigenesis in mice. We show that SARI is a novel inhibitor of colon tumour growth and angiogenesis in mice. Antibody array and HUVEC-related assays indicate that VEGF has an essential role in SARI-controlled inhibition of angiogenesis. Furthermore, Co-IP/PAGE/mass spectrometry indicates that SARI directly targets ceruloplasmin (Cp), and induces protease degradation of Cp, thereby inhibiting the activity of the HIF-1α/VEGF axis. Tissue microarray results indicate that SARI expression inversely correlates with poor clinical outcomes in colon cancer patients. Collectively, our results indicate that SARI is a potential target for therapy by inhibiting angiogenesis through the reduction of VEGF expression and is a prognostic indicator for patients with colon cancer. PMID:27353863

  3. SARI inhibits angiogenesis and tumour growth of human colon cancer through directly targeting ceruloplasmin

    PubMed Central

    Dai, Lei; Cui, Xueliang; Zhang, Xin; Cheng, Lin; Liu, Yi; Yang, Yang; Fan, Ping; Wang, Qingnan; Lin, Yi; Zhang, Junfeng; Li, Chunlei; Mao, Ying; Wang, Qin; Su, Xiaolan; Zhang, Shuang; Peng, Yong; Yang, Hanshuo; Hu, Xun; Yang, Jinliang; Huang, Meijuan; Xiang, Rong; Yu, Dechao; Zhou, Zongguang; Wei, Yuquan; Deng, Hongxin

    2016-01-01

    SARI, also called as BATF2, belongs to the BATF family and has been implicated in cancer cell growth inhibition. However, the role and mechanism of SARI in tumour angiogenesis are elusive. Here we demonstrate that SARI deficiency facilitates AOM/DSS-induced colonic tumorigenesis in mice. We show that SARI is a novel inhibitor of colon tumour growth and angiogenesis in mice. Antibody array and HUVEC-related assays indicate that VEGF has an essential role in SARI-controlled inhibition of angiogenesis. Furthermore, Co-IP/PAGE/mass spectrometry indicates that SARI directly targets ceruloplasmin (Cp), and induces protease degradation of Cp, thereby inhibiting the activity of the HIF-1α/VEGF axis. Tissue microarray results indicate that SARI expression inversely correlates with poor clinical outcomes in colon cancer patients. Collectively, our results indicate that SARI is a potential target for therapy by inhibiting angiogenesis through the reduction of VEGF expression and is a prognostic indicator for patients with colon cancer. PMID:27353863

  4. DCC constrains tumour progression via its dependence receptor activity.

    PubMed

    Castets, Marie; Broutier, Laura; Molin, Yann; Brevet, Marie; Chazot, Guillaume; Gadot, Nicolas; Paquet, Armelle; Mazelin, Laetitia; Jarrosson-Wuilleme, Loraine; Scoazec, Jean-Yves; Bernet, Agnès; Mehlen, Patrick

    2012-02-23

    The role of deleted in colorectal carcinoma (DCC) as a tumour suppressor has been a matter of debate for the past 15 years. DCC gene expression is lost or markedly reduced in the majority of advanced colorectal cancers and, by functioning as a dependence receptor, DCC has been shown to induce apoptosis unless engaged by its ligand, netrin-1 (ref. 2). However, so far no animal model has supported the view that the DCC loss-of-function is causally implicated as predisposing to aggressive cancer development. To investigate the role of DCC-induced apoptosis in the control of tumour progression, here we created a mouse model in which the pro-apoptotic activity of DCC is genetically silenced. Although the loss of DCC-induced apoptosis in this mouse model is not associated with a major disorganization of the intestines, it leads to spontaneous intestinal neoplasia at a relatively low frequency. Loss of DCC-induced apoptosis is also associated with an increase in the number and aggressiveness of intestinal tumours in a predisposing APC mutant context, resulting in the development of highly invasive adenocarcinomas. These results demonstrate that DCC functions as a tumour suppressor via its ability to trigger tumour cell apoptosis. PMID:22158121

  5. Src activation by β-adrenoreceptors is a key switch for tumour metastasis.

    PubMed

    Armaiz-Pena, Guillermo N; Allen, Julie K; Cruz, Anthony; Stone, Rebecca L; Nick, Alpa M; Lin, Yvonne G; Han, Liz Y; Mangala, Lingegowda S; Villares, Gabriel J; Vivas-Mejia, Pablo; Rodriguez-Aguayo, Cristian; Nagaraja, Archana S; Gharpure, Kshipra M; Wu, Zheng; English, Robert D; Soman, Kizhake V; Shahzad, Mian M K; Shazhad, Mian M K; Zigler, Maya; Deavers, Michael T; Zien, Alexander; Soldatos, Theodoros G; Jackson, David B; Wiktorowicz, John E; Torres-Lugo, Madeline; Young, Tom; De Geest, Koen; Gallick, Gary E; Bar-Eli, Menashe; Lopez-Berestein, Gabriel; Cole, Steve W; Lopez, Gustavo E; Lutgendorf, Susan K; Sood, Anil K

    2013-01-01

    Noradrenaline can modulate multiple cellular functions important for cancer progression; however, how this single extracellular signal regulates such a broad array of cellular processes is unknown. Here we identify Src as a key regulator of phosphoproteomic signalling networks activated in response to beta-adrenergic signalling in cancer cells. These results also identify a new mechanism of Src phosphorylation that mediates beta-adrenergic/PKA regulation of downstream networks, thereby enhancing tumour cell migration, invasion and growth. In human ovarian cancer samples, high tumoural noradrenaline levels were correlated with high pSrc(Y419) levels. Moreover, among cancer patients, the use of beta blockers was significantly associated with reduced cancer-related mortality. Collectively, these data provide a pivotal molecular target for disrupting neural signalling in the tumour microenvironment. PMID:23360994

  6. Targeting breast to brain metastatic tumours with death receptor ligand expressing therapeutic stem cells

    PubMed Central

    Bagci-Onder, Tugba; Du, Wanlu; Figueiredo, Jose-Luiz; Martinez-Quintanilla, Jordi

    2015-01-01

    Characterizing clinically relevant brain metastasis models and assessing the therapeutic efficacy in such models are fundamental for the development of novel therapies for metastatic brain cancers. In this study, we have developed an in vivo imageable breast-to-brain metastasis mouse model. Using real time in vivo imaging and subsequent composite fluorescence imaging, we show a widespread distribution of micro- and macro-metastasis in different stages of metastatic progression. We also show extravasation of tumour cells and the close association of tumour cells with blood vessels in the brain thus mimicking the multi-foci metastases observed in the clinics. Next, we explored the ability of engineered adult stem cells to track metastatic deposits in this model and show that engineered stem cells either implanted or injected via circulation efficiently home to metastatic tumour deposits in the brain. Based on the recent findings that metastatic tumour cells adopt unique mechanisms of evading apoptosis to successfully colonize in the brain, we reasoned that TNF receptor superfamily member 10A/10B apoptosis-inducing ligand (TRAIL) based pro-apoptotic therapies that induce death receptor signalling within the metastatic tumour cells might be a favourable therapeutic approach. We engineered stem cells to express a tumour selective, potent and secretable variant of a TRAIL, S-TRAIL, and show that these cells significantly suppressed metastatic tumour growth and prolonged the survival of mice bearing metastatic breast tumours. Furthermore, the incorporation of pro-drug converting enzyme, herpes simplex virus thymidine kinase, into therapeutic S-TRAIL secreting stem cells allowed their eradication post-tumour treatment. These studies are the first of their kind that provide insight into targeting brain metastasis with stem-cell mediated delivery of pro-apoptotic ligands and have important clinical implications. PMID:25910782

  7. Reaching a Moveable Visual Target: Dissociations in Brain Tumour Patients

    ERIC Educational Resources Information Center

    Buiatti, Tania; Skrap, Miran; Shallice, Tim

    2013-01-01

    Damage to the posterior parietal cortex (PPC) can lead to Optic Ataxia (OA), in which patients misreach to peripheral targets. Recent research suggested that the PPC might be involved not only in simple reaching tasks toward peripheral targets, but also in changing the hand movement trajectory in real time if the target moves. The present study…

  8. Genes implicated in stem cell identity and temporal programme are directly targeted by Notch in neuroblast tumours

    PubMed Central

    Zacharioudaki, Evanthia; Housden, Benjamin E.; Garinis, George; Stojnic, Robert; Delidakis, Christos; Bray, Sarah J.

    2016-01-01

    Notch signalling is involved in a multitude of developmental decisions and its aberrant activation is linked to many diseases, including cancers. One example is the neural stem cell tumours that arise from constitutive Notch activity in Drosophila neuroblasts. To investigate how hyperactivation of Notch in larval neuroblasts leads to tumours, we combined results from profiling the upregulated mRNAs and mapping the regions bound by the core Notch pathway transcription factor Su(H). This identified 246 putative direct Notch targets. These genes were highly enriched for transcription factors and overlapped significantly with a previously identified regulatory programme dependent on the proneural transcription factor Asense. Included were genes associated with the neuroblast maintenance and self-renewal programme that we validated as Notch regulated in vivo. Another group were the so-called temporal transcription factors, which have been implicated in neuroblast maturation. Normally expressed in specific time windows, several temporal transcription factors were ectopically expressed in the stem cell tumours, suggesting that Notch had reprogrammed their normal temporal regulation. Indeed, the Notch-induced hyperplasia was reduced by mutations affecting two of the temporal factors, which, conversely, were sufficient to induce mild hyperplasia on their own. Altogether, the results suggest that Notch induces neuroblast tumours by directly promoting the expression of genes that contribute to stem cell identity and by reprogramming the expression of factors that could regulate maturity. PMID:26657768

  9. Triple-Modal Imaging of Magnetically-Targeted Nanocapsules in Solid Tumours In Vivo.

    PubMed

    Bai, Jie; Wang, Julie T-W; Rubio, Noelia; Protti, Andrea; Heidari, Hamed; Elgogary, Riham; Southern, Paul; Al-Jamal, Wafa' T; Sosabowski, Jane; Shah, Ajay M; Bals, Sara; Pankhurst, Quentin A; Al-Jamal, Khuloud T

    2016-01-01

    Triple-modal imaging magnetic nanocapsules, encapsulating hydrophobic superparamagnetic iron oxide nanoparticles, are formulated and used to magnetically target solid tumours after intravenous administration in tumour-bearing mice. The engineered magnetic polymeric nanocapsules m-NCs are ~200 nm in size with negative Zeta potential and shown to be spherical in shape. The loading efficiency of superparamagnetic iron oxide nanoparticles in the m-NC was ~100%. Up to ~3- and ~2.2-fold increase in tumour uptake at 1 and 24 h was achieved, when a static magnetic field was applied to the tumour for 1 hour. m-NCs, with multiple imaging probes (e.g. indocyanine green, superparamagnetic iron oxide nanoparticles and indium-111), were capable of triple-modal imaging (fluorescence/magnetic resonance/nuclear imaging) in vivo. Using triple-modal imaging is to overcome the intrinsic limitations of single modality imaging and provides complementary information on the spatial distribution of the nanocarrier within the tumour. The significant findings of this study could open up new research perspectives in using novel magnetically-responsive nanomaterials in magnetic-drug targeting combined with multi-modal imaging. PMID:26909110

  10. Triple-Modal Imaging of Magnetically-Targeted Nanocapsules in Solid Tumours In Vivo

    PubMed Central

    Bai, Jie; Wang, Julie T.-W.; Rubio, Noelia; Protti, Andrea; Heidari, Hamed; Elgogary, Riham; Southern, Paul; Al-Jamal, Wafa' T.; Sosabowski, Jane; Shah, Ajay M.; Bals, Sara; Pankhurst, Quentin A.; Al-Jamal, Khuloud T.

    2016-01-01

    Triple-modal imaging magnetic nanocapsules, encapsulating hydrophobic superparamagnetic iron oxide nanoparticles, are formulated and used to magnetically target solid tumours after intravenous administration in tumour-bearing mice. The engineered magnetic polymeric nanocapsules m-NCs are ~200 nm in size with negative Zeta potential and shown to be spherical in shape. The loading efficiency of superparamagnetic iron oxide nanoparticles in the m-NC was ~100%. Up to ~3- and ~2.2-fold increase in tumour uptake at 1 and 24 h was achieved, when a static magnetic field was applied to the tumour for 1 hour. m-NCs, with multiple imaging probes (e.g. indocyanine green, superparamagnetic iron oxide nanoparticles and indium-111), were capable of triple-modal imaging (fluorescence/magnetic resonance/nuclear imaging) in vivo. Using triple-modal imaging is to overcome the intrinsic limitations of single modality imaging and provides complementary information on the spatial distribution of the nanocarrier within the tumour. The significant findings of this study could open up new research perspectives in using novel magnetically-responsive nanomaterials in magnetic-drug targeting combined with multi-modal imaging. PMID:26909110

  11. Tumour suppressor HLJ1: A potential diagnostic, preventive and therapeutic target in non-small cell lung cancer

    PubMed Central

    Tsai, Meng-Feng; Wang, Chi-Chung; Chen, Jeremy JW

    2014-01-01

    Lung cancer is the leading cause of cancer-related mortality throughout the world. Non-small cell lung cancer (NSCLC) accounts for 85% of all diagnosed lung cancers. Despite considerable progress in the diagnosis and treatment of the disease, the overall 5-year survival rate of NSCLC patients remains lower than 15%. The most common causes of death in lung cancer patients are treatment failure and metastasis. Therefore, developing novel strategies that target both tumour growth and metastasis is an important and urgent mission for the next generation of anticancer therapy research. Heat shock proteins (HSPs), which are involved in the fundamental defence mechanism for maintaining cellular viability, are markedly activated during environmental or pathogenic stress. HSPs facilitate rapid cell division, metastasis, and the evasion of apoptosis in cancer development. These proteins are essential players in the development of cancer and are prime therapeutic targets. In this review, we focus on the current understanding of the molecular mechanisms responsible for HLJ1’s role in lung cancer carcinogenesis and progression. HLJ1, a member of the human HSP 40 family, has been characterised as a tumour suppressor. Research studies have also reported that HLJ1 shows promising dual anticancer effects, inhibiting both tumour growth and metastasis in NSCLC. The accumulated evidence suggests that HLJ1 is a potential biomarker and treatment target for NSCLC. PMID:25493224

  12. A G-quadruplex-binding compound showing anti-tumour activity in an in vivo model for pancreatic cancer

    PubMed Central

    Ohnmacht, Stephan A; Marchetti, Chiara; Gunaratnam, Mekala; Besser, Rachael J; Haider, Shozeb M; Di Vita, Gloria; Lowe, Helen L; Mellinas-Gomez, Maria; Diocou, Seckou; Robson, Mathew; Šponer, Jiri; Islam, Barira; Barbara Pedley, R; Hartley, John A; Neidle, Stephen

    2015-01-01

    We report here that a tetra-substituted naphthalene-diimide derivative (MM41) has significant in vivo anti-tumour activity against the MIA PaCa-2 pancreatic cancer xenograft model. IV administration with a twice-weekly 15 mg/kg dose produces ca 80% tumour growth decrease in a group of tumour-bearing animals. Two animals survived tumour-free after 279 days. High levels of MM41 are rapidly transported into cell nuclei and were found to accumulate in the tumour. MM41 is a quadruplex-interactive compound which binds strongly to the quadruplexes encoded in the promoter sequences of the BCL-2 and k-RAS genes, both of which are dis-regulated in many human pancreatic cancers. Levels of BCL-2 were reduced by ca 40% in tumours from MM41-treated animals relative to controls, consistent with BCL-2 being a target for MM41. Molecular modelling suggests that MM41 binds to a BCL-2 quadruplex in a manner resembling that previously observed in co-crystal structures with human telomeric quadruplexes. This supports the concept that MM41 (and by implication other quadruplex-targeting small molecules) can bind to quadruplex-forming promoter regions in a number of genes and down-regulate their transcription. We suggest that quadruplexes within those master genes that are up-regulated drivers for particular cancers, may be selective targets for compounds such as MM41. PMID:26077929

  13. A G-quadruplex-binding compound showing anti-tumour activity in an in vivo model for pancreatic cancer.

    PubMed

    Ohnmacht, Stephan A; Marchetti, Chiara; Gunaratnam, Mekala; Besser, Rachael J; Haider, Shozeb M; Di Vita, Gloria; Lowe, Helen L; Mellinas-Gomez, Maria; Diocou, Seckou; Robson, Mathew; Šponer, Jiri; Islam, Barira; Pedley, R Barbara; Hartley, John A; Neidle, Stephen

    2015-01-01

    We report here that a tetra-substituted naphthalene-diimide derivative (MM41) has significant in vivo anti-tumour activity against the MIA PaCa-2 pancreatic cancer xenograft model. IV administration with a twice-weekly 15 mg/kg dose produces ca 80% tumour growth decrease in a group of tumour-bearing animals. Two animals survived tumour-free after 279 days. High levels of MM41 are rapidly transported into cell nuclei and were found to accumulate in the tumour. MM41 is a quadruplex-interactive compound which binds strongly to the quadruplexes encoded in the promoter sequences of the BCL-2 and k-RAS genes, both of which are dis-regulated in many human pancreatic cancers. Levels of BCL-2 were reduced by ca 40% in tumours from MM41-treated animals relative to controls, consistent with BCL-2 being a target for MM41. Molecular modelling suggests that MM41 binds to a BCL-2 quadruplex in a manner resembling that previously observed in co-crystal structures with human telomeric quadruplexes. This supports the concept that MM41 (and by implication other quadruplex-targeting small molecules) can bind to quadruplex-forming promoter regions in a number of genes and down-regulate their transcription. We suggest that quadruplexes within those master genes that are up-regulated drivers for particular cancers, may be selective targets for compounds such as MM41. PMID:26077929

  14. Display of GPI-anchored anti-EGFR nanobodies on extracellular vesicles promotes tumour cell targeting

    PubMed Central

    Kooijmans, Sander A. A.; Aleza, Clara Gómez; Roffler, Steve R.; van Solinge, Wouter W.; Vader, Pieter; Schiffelers, Raymond M.

    2016-01-01

    Background Extracellular vesicles (EVs) are attractive candidate drug delivery systems due to their ability to functionally transport biological cargo to recipient cells. However, the apparent lack of target cell specificity of exogenously administered EVs limits their therapeutic applicability. In this study, we propose a novel method to equip EVs with targeting properties, in order to improve their interaction with tumour cells. Methods EV producing cells were transfected with vectors encoding for anti-epidermal growth factor receptor (EGFR) nanobodies, which served as targeting ligands for tumour cells, fused to glycosylphosphatidylinositol (GPI) anchor signal peptides derived from decay-accelerating factor (DAF). EVs were isolated using ultrafiltration/size-exclusion liquid chromatography and characterized using western blotting, Nanoparticle Tracking Analysis, and electron microscopy. EV–tumour cell interactions were analyzed under static conditions using flow cytometry and under flow conditions using a live-cell fluorescence microscopy-coupled perfusion system. Results EV analysis showed that GPI-linked nanobodies were successfully displayed on EV surfaces and were highly enriched in EVs compared with parent cells. Display of GPI-linked nanobodies on EVs did not alter general EV characteristics (i.e. morphology, size distribution and protein marker expression), but greatly improved EV binding to tumour cells dependent on EGFR density under static conditions. Moreover, nanobody-displaying EVs showed a significantly improved cell association to EGFR-expressing tumour cells under flow conditions. Conclusions We show that nanobodies can be anchored on the surface of EVs via GPI, which alters their cell targeting behaviour. Furthermore, this study highlights GPI-anchoring as a new tool in the EV toolbox, which may be applied for EV display of a variety of proteins, such as antibodies, reporter proteins and signaling molecules. PMID:26979463

  15. Lysyl oxidase-like-2 promotes tumour angiogenesis and is a potential therapeutic target in angiogenic tumours.

    PubMed

    Zaffryar-Eilot, Shelly; Marshall, Derek; Voloshin, Tali; Bar-Zion, Avinoam; Spangler, Rhyannon; Kessler, Ofra; Ghermazien, Haben; Brekhman, Vera; Suss-Toby, Edith; Adam, Dan; Shaked, Yuval; Smith, Victoria; Neufeld, Gera

    2013-10-01

    Lysyl oxidase-like 2 (LOXL2), a secreted enzyme that catalyzes the cross-linking of collagen, plays an essential role in developmental angiogenesis. We found that administration of the LOXL2-neutralizing antibody AB0023 inhibited bFGF-induced angiogenesis in Matrigel plug assays and suppressed recruitment of angiogenesis promoting bone marrow cells. Small hairpin RNA-mediated inhibition of LOXL2 expression or inhibition of LOXL2 using AB0023 reduced the migration and network-forming ability of endothelial cells, suggesting that the inhibition of angiogenesis results from a direct effect on endothelial cells. To examine the effects of AB0023 on tumour angiogenesis, AB0023 was administered to mice bearing tumours derived from SKOV-3 ovarian carcinoma or Lewis lung carcinoma (LLC) cells. AB0023 treatment significantly reduced the microvascular density in these tumours but did not inhibit tumour growth. However, treatment of mice bearing SKOV-3-derived tumours with AB0023 also promoted increased coverage of tumour vessels with pericytes and reduced tumour hypoxia, providing evidence that anti-LOXL2 therapy results in the normalization of tumour blood vessels. In agreement with these data, treatment of mice bearing LLC-derived tumours with AB0023 improved the perfusion of the tumour-associated vessels as determined by ultrasonography. Improved perfusion and normalization of tumour vessels after treatment with anti-angiogenic agents were previously found to improve the delivery of chemotherapeutic agents into tumours and to result in an enhancement of chemotherapeutic efficiency. Indeed, treatment with AB0023 significantly enhanced the anti-tumourigenic effects of taxol. Our results suggest that inhibition of LOXL2 may prove beneficial for the treatment of angiogenic tumours. PMID:23828904

  16. Somatic DNA mutation analysis in targeted therapy of solid tumours

    PubMed Central

    O’Toole, Sandra A.; Trent, Ronald J.

    2015-01-01

    Cancer is a disease of the genome with diverse aetiologies including the accumulation of acquired mutations throughout the genome. There has been a flood of knowledge improving our understanding of the biology and molecular genetics of melanoma, lung and colorectal cancer since the genomics era started. Translation of this knowledge into a better understanding of cell proliferation, survival and apoptosis has produced a paradigm shift in medical oncology enabling gene-based cancer treatment (called personalised or precision medicine). Somatic mutation analysis is crucial for a genomics approach since it can identify driver mutations—the “Achilles’ heel” of cancer, and support clinical decision-making through targeted therapy. Nevertheless, the applications of somatic DNA testing in cancer face many challenges such as obtaining comprehensive coverage of the cancer genome with limited DNA being available, and delivering an accurate report in a timely fashion without false-negative and false-positive results. Further advances in DNA technologies and bioinformatics will overcome these issues and maximise opportunities for targeted therapy. Somatic mutation analysis will then become an integral part of cancer management for all malignancies. PMID:26835368

  17. Activation and repression by oncogenic MYC shape tumour-specific gene expression profiles.

    PubMed

    Walz, Susanne; Lorenzin, Francesca; Morton, Jennifer; Wiese, Katrin E; von Eyss, Björn; Herold, Steffi; Rycak, Lukas; Dumay-Odelot, Hélène; Karim, Saadia; Bartkuhn, Marek; Roels, Frederik; Wüstefeld, Torsten; Fischer, Matthias; Teichmann, Martin; Zender, Lars; Wei, Chia-Lin; Sansom, Owen; Wolf, Elmar; Eilers, Martin

    2014-07-24

    In mammalian cells, the MYC oncoprotein binds to thousands of promoters. During mitogenic stimulation of primary lymphocytes, MYC promotes an increase in the expression of virtually all genes. In contrast, MYC-driven tumour cells differ from normal cells in the expression of specific sets of up- and downregulated genes that have considerable prognostic value. To understand this discrepancy, we studied the consequences of inducible expression and depletion of MYC in human cells and murine tumour models. Changes in MYC levels activate and repress specific sets of direct target genes that are characteristic of MYC-transformed tumour cells. Three factors account for this specificity. First, the magnitude of response parallels the change in occupancy by MYC at each promoter. Functionally distinct classes of target genes differ in the E-box sequence bound by MYC, suggesting that different cellular responses to physiological and oncogenic MYC levels are controlled by promoter affinity. Second, MYC both positively and negatively affects transcription initiation independent of its effect on transcriptional elongation. Third, complex formation with MIZ1 (also known as ZBTB17) mediates repression of multiple target genes by MYC and the ratio of MYC and MIZ1 bound to each promoter correlates with the direction of response. PMID:25043018

  18. Tumour progression and metastasis.

    PubMed

    Arvelo, Francisco; Sojo, Felipe; Cotte, Carlos

    2016-01-01

    The two biological mechanisms that determine types of malignancy are infiltration and metastasis, for which tumour microenvironment plays a key role in developing and establishing the morphology, growth and invasiveness of a malignancy. The microenvironment is formed by complex tissue containing the extracellular matrix, tumour and non-tumour cells, a signalling network of cytokines, chemokines, growth factors, and proteases that control autocrine and paracrine communication among individual cells, facilitating tumour progression. During the development of the primary tumour, the tumour stroma and continuous genetic changes within the cells makes it possible for them to migrate, having to count on a pre-metastatic niche receptor that allows the tumour's survival and distant growth. These niches are induced by factors produced by the primary tumour; if it is eradicated, the active niches become responsible for activating the latent disseminated cells. Due to the importance of these mechanisms, the strategies that develop tumour cells during tumour progression and the way in which the microenvironment influences the formation of metastasis are reviewed. It also suggests that the metastatic niche can be an ideal target for new treatments that make controlling metastasis possible. PMID:26913068

  19. Dissection of tumour and host cells from target organs of metastasis for testing gene expression directly ex vivo.

    PubMed Central

    Rocha, M.; Hexel, K.; Bucur, M.; Schirrmacher, V.; Umansky, V.

    1996-01-01

    We report on a new methodology which allows the direct analysis ex vivo of tumour cells and host cells (lymphocytes, macrophages, endothelial cells) from a metastasised organ (liver or spleen) at any time point during the metastatic process and without any further in vitro culture. First, we used a tumour cell line transduced with the bacterial gene lacZ, which permits the detection of the procaryotic enzyme beta-galactosidase in eukaryotic cells at the single cell level thus allowing flow adhesion cell sorting (FACS) analysis of tumour cells from metastasised target organs. Second, we established a method for the separation and enrichment of tumour and host cells from target organs of metastasis with a high viability and reproducibility. As exemplified with the murine lymphoma ESb, this new methodology permits the study of molecules of importance for metastasis or anti-tumour immunity (adhesion, costimulatory and cytotoxic molecules, cytokines, etc.) at the RNA or protein level in tumour and host cells during the whole process of metastasis. This novel approach may open new possibilities of developing strategies for intervention in tumour progression, since it allows the determination of the optimal window in time for successful treatments. The possibility of direct analysis of tumour and host cell properties also provides a new method for the evaluation of the effects of immunisation with tumour vaccines or of gene therapy. Images Figure 3 PMID:8883407

  20. Anti - tumour activity of an ayurvedic oil preparation.

    PubMed

    Panikar, K R; Bhanumathy, P; Raghunath, P N

    1986-10-01

    An ayurvedic oil preparation containing flowers of ixora coccinea and cortus sativum was subjected to an animal experimentation to find out how far it is efficient in preventing the development of Dalton's lymphoma as solid tumour. The oil was applied after injecting the cells and we found it could retard the development of tumour and arrest further development of already formed tumour. PMID:22557556

  1. ANTI – TUMOUR ACTIVITY OF AN AYURVEDIC OIL PREPARATION

    PubMed Central

    Panikar, K. R.; Bhanumathy, P.; Raghunath, P. N.

    1986-01-01

    An ayurvedic oil preparation containing flowers of ixora coccinea and cortus sativum was subjected to an animal experimentation to find out how far it is efficient in preventing the development of Dalton's lymphoma as solid tumour. The oil was applied after injecting the cells and we found it could retard the development of tumour and arrest further development of already formed tumour. PMID:22557556

  2. Investigation of the effect of physical parameters on the design of tumour targeting agents

    NASA Astrophysics Data System (ADS)

    Casey, Joanne Lois

    Tumour targeting using radiolabelled antibodies for radioimmunodetection (RAID) and radioimmunotherapy (RIT) has been studied for many years. The main factors that have limited clinical success are low tumour uptake, immunogenicity and poor therapeutic ratios. This thesis has applied current technology to make advances in this area of research. The effect of physical parameters (antibody size, valency, affinity and charge) on the design of tumour targeting agents was studied by constructing divalent (DFM) and trivalent (TFM) forms of the murine anti-CEA antibody A5B7 Fab' by chemical cross-linking. This involves partial reduction of the hinge disulphides to expose thiol (-SH) groups and subsequent reaction with a maleimide cross-linker to form a thioether bond at the hinge region. Previous studies have suggested that the stability of thioether bonds is superior to naturally occurring disulphide bonds present at the hinge region of IgG and F(ab')2. The aim was to compare the functional affinities and in vivo tumour targeting in nude mice bearing human tumour xenografts of DFM and TFM to similar sized parent IgG and F(ab')2. Radiolabelling with 131I and 90Y was also compared with a view to determine which combination would be optimal for RIT. Results clearly demonstrated a significantly faster on-rate of DFM compared to all other antibody forms and estimated dosimetry analysis suggested that DFM would be the most suitable antibody form radiolabelled with 131I for RIT. Both F(ab')2 and DFM showed high kidney uptake levels on labelling with which is unacceptable for RIT. Despite the improved tumour: blood ratios for TFM, the increased estimated dose to normal tissues and lower therapeutic effect in RIT studies suggests that the most promising combination with the radionuclide appears to be IgG. A humanised version of A5B7 hFab' has been constructed previously in order to reduce its immunogenicity in man. The in vivo stability of hDFM proved to be superior to hF(ab')2

  3. Target activated frame capture

    NASA Astrophysics Data System (ADS)

    Roberts, G. Marlon; Fitzgerald, James; McCormack, Michael; Steadman, Robert

    2008-04-01

    Over the past decade, technological advances have enabled the use of increasingly intelligent systems for battlefield surveillance. These systems are triggered by a combination of external devices including acoustic and seismic sensors. Such products are mainly used to detect vehicles and personnel. These systems often use infra-red imagery to record environmental information, but Textron Defense Systems' Terrain Commander is one of a small number of systems which analyze these images for the presence of targets. The Terrain Commander combines acoustic, infrared, magnetic, seismic, and visible spectrum sensors to detect nearby targets in military scenarios. When targets are detected by these sensors, the cameras are triggered and images are captured in the infrared and visible spectrum. In this paper we discuss a method through which such systems can perform target tracking in order to record and transmit only the most pertinent surveillance images. This saves bandwidth which is crucial because these systems often use communication systems with throughputs below 2400bps. This method is expected to be executable on low-power processors at frame rates exceeding 10HZ. We accomplish this by applying target activated frame capture algorithms to infra-red video data. The target activated frame capture algorithms combine edge detection and motion detection to determine the best frames to be transmitted to the end user. This keeps power consumption and bandwidth requirements low. Finally, the results of the algorithm are analyzed.

  4. Tumour progression and metastasis

    PubMed Central

    Arvelo, Francisco; Sojo, Felipe; Cotte, Carlos

    2016-01-01

    The two biological mechanisms that determine types of malignancy are infiltration and metastasis, for which tumour microenvironment plays a key role in developing and establishing the morphology, growth and invasiveness of a malignancy. The microenvironment is formed by complex tissue containing the extracellular matrix, tumour and non-tumour cells, a signalling network of cytokines, chemokines, growth factors, and proteases that control autocrine and paracrine communication among individual cells, facilitating tumour progression. During the development of the primary tumour, the tumour stroma and continuous genetic changes within the cells makes it possible for them to migrate, having to count on a pre-metastatic niche receptor that allows the tumour’s survival and distant growth. These niches are induced by factors produced by the primary tumour; if it is eradicated, the active niches become responsible for activating the latent disseminated cells. Due to the importance of these mechanisms, the strategies that develop tumour cells during tumour progression and the way in which the microenvironment influences the formation of metastasis are reviewed. It also suggests that the metastatic niche can be an ideal target for new treatments that make controlling metastasis possible. PMID:26913068

  5. Mitogen-activated Tasmanian devil blood mononuclear cells kill devil facial tumour disease cells.

    PubMed

    Brown, Gabriella K; Tovar, Cesar; Cooray, Anne A; Kreiss, Alexandre; Darby, Jocelyn; Murphy, James M; Corcoran, Lynn M; Bettiol, Silvana S; Lyons, A Bruce; Woods, Gregory M

    2016-08-01

    Devil facial tumour disease (DFTD) is a transmissible cancer that has brought the host species, the Tasmanian devil, to the brink of extinction. The cancer cells avoid allogeneic immune recognition by downregulating cell surface major histocompatibility complex (MHC) I expression. This should prevent CD8(+) T cell, but not natural killer (NK) cell, cytotoxicity. The reason why NK cells, normally reactive to MHC-negative cells, are not activated to kill DFTD cells has not been determined. The immune response of wild devils to DFTD, if it occurs, is uncharacterised. To investigate this, we tested 12 wild devils with DFTD, and found suggestive evidence of low levels of antibodies against DFTD cells in one devil. Eight of these devils were also analysed for cytotoxicity, however, none showed evidence for cytotoxicity against cultured DFTD cells. To establish whether mimicking activation of antitumour responses could induce cytotoxic activity against DFTD, Tasmanian devil peripheral blood mononuclear cells (PBMCs) were treated with either the mitogen Concanavalin A, the Toll-like receptor agonist polyinosinic:polycytidylic acid or recombinant Tasmanian devil IL-2. All induced the PBMC cells to kill cultured DFTD cells, suggesting that activation does not occur after encounter with DFTD cells in vivo, but can be induced. The identification of agents that activate cytotoxicity against DFTD target cells is critical for developing strategies to protect against DFTD. Such agents could function as adjuvants to induce functional immune responses capable of targeting DFTD cells and tumours in vivo. PMID:27089941

  6. Role of the microtubule-targeting drug vinflunine on cell-cell adhesions in bladder epithelial tumour cells

    PubMed Central

    2014-01-01

    Background Vinflunine (VFL) is a microtubule-targeting drug that suppresses microtubule dynamics, showing anti-metastatic properties both in vitro and in living cancer cells. An increasing body of evidence underlines the influence of the microtubules dynamics on the cadherin-dependent cell-cell adhesions. E-cadherin is a marker of epithelial-to-mesenchymal transition (EMT) and a tumour suppressor; its reduced levels in carcinoma are associated with poor prognosis. In this report, we investigate the role of VFL on cell-cell adhesions in bladder epithelial tumour cells. Methods Human bladder epithelial tumour cell lines HT1376, 5637, SW780, T24 and UMUC3 were used to analyse cadherin-dependent cell-cell adhesions under VFL treatment. VFL effect on growth inhibition was measured by using a MTT colorimetric cell viability assay. Western blot, immunofluorescence and transmission electron microscopy analyses were performed to assess the roles of VFL effect on cell-cell adhesions, epithelial-to-mesenchymal markers and apoptosis. The role of the proteasome in controlling cell-cell adhesion was studied using the proteasome inhibitor MG132. Results We show that VFL induces cell death in bladder cancer cells and activates epithelial differentiation of the remaining living cells, leading to an increase of E-cadherin-dependent cell-cell adhesion and a reduction of mesenchymal markers, such as N-cadherin or vimentin. Moreover, while E-cadherin is increased, the levels of Hakai, an E3 ubiquitin-ligase for E-cadherin, were significantly reduced in presence of VFL. In 5637, this reduction on Hakai expression was blocked by MG132 proteasome inhibitor, indicating that the proteasome pathway could be one of the molecular mechanisms involved in its degradation. Conclusions Our findings underscore a critical function for VFL in cell-cell adhesions of epithelial bladder tumour cells, suggesting a novel molecular mechanism by which VFL may impact upon EMT and metastasis. PMID:25012153

  7. Targeting tumour hypoxia to prevent cancer metastasis. From biology, biosensing and technology to drug development: the METOXIA consortium.

    PubMed

    Pettersen, Erik O; Ebbesen, Peter; Gieling, Roben G; Williams, Kaye J; Dubois, Ludwig; Lambin, Philippe; Ward, Carol; Meehan, James; Kunkler, Ian H; Langdon, Simon P; Ree, Anne H; Flatmark, Kjersti; Lyng, Heidi; Calzada, Maria J; Peso, Luis Del; Landazuri, Manuel O; Görlach, Agnes; Flamm, Hubert; Kieninger, Jochen; Urban, Gerald; Weltin, Andreas; Singleton, Dean C; Haider, Syed; Buffa, Francesca M; Harris, Adrian L; Scozzafava, Andrea; Supuran, Claudiu T; Moser, Isabella; Jobst, Gerhard; Busk, Morten; Toustrup, Kasper; Overgaard, Jens; Alsner, Jan; Pouyssegur, Jacques; Chiche, Johanna; Mazure, Nathalie; Marchiq, Ibtissam; Parks, Scott; Ahmed, Afshan; Ashcroft, Margaret; Pastorekova, Silvia; Cao, Yihai; Rouschop, Kasper M; Wouters, Brad G; Koritzinsky, Marianne; Mujcic, Hilda; Cojocari, Dan

    2015-01-01

    The hypoxic areas of solid cancers represent a negative prognostic factor irrespective of which treatment modality is chosen for the patient. Still, after almost 80 years of focus on the problems created by hypoxia in solid tumours, we still largely lack methods to deal efficiently with these treatment-resistant cells. The consequences of this lack may be serious for many patients: Not only is there a negative correlation between the hypoxic fraction in tumours and the outcome of radiotherapy as well as many types of chemotherapy, a correlation has been shown between the hypoxic fraction in tumours and cancer metastasis. Thus, on a fundamental basis the great variety of problems related to hypoxia in cancer treatment has to do with the broad range of functions oxygen (and lack of oxygen) have in cells and tissues. Therefore, activation-deactivation of oxygen-regulated cascades related to metabolism or external signalling are important areas for the identification of mechanisms as potential targets for hypoxia-specific treatment. Also the chemistry related to reactive oxygen radicals (ROS) and the biological handling of ROS are part of the problem complex. The problem is further complicated by the great variety in oxygen concentrations found in tissues. For tumour hypoxia to be used as a marker for individualisation of treatment there is a need for non-invasive methods to measure oxygen routinely in patient tumours. A large-scale collaborative EU-financed project 2009-2014 denoted METOXIA has studied all the mentioned aspects of hypoxia with the aim of selecting potential targets for new hypoxia-specific therapy and develop the first stage of tests for this therapy. A new non-invasive PET-imaging method based on the 2-nitroimidazole [(18)F]-HX4 was found to be promising in a clinical trial on NSCLC patients. New preclinical models for testing of the metastatic potential of cells were developed, both in vitro (2D as well as 3D models) and in mice (orthotopic grafting

  8. Biodegradable interstitial release polymer loading a novel small molecule targeting Axl receptor tyrosine kinase and reducing brain tumour migration and invasion

    PubMed Central

    Yen, S-Y; Chen, S-R; Hsieh, J; Li, Y-S; Chuang, S-E; Chuang, H-M; Huang, M-H; Lin, S-Z; Harn, H-J; Chiou, T-W

    2016-01-01

    Glioblastoma multiforme (GBM) is the most common and aggressive brain tumour. The neoplasms are difficult to resect entirely because of their highly infiltration property and leading to the tumour edge is unclear. Gliadel wafer has been used as an intracerebral drug delivery system to eliminate the residual tumour. However, because of its local low concentration and short diffusion distance, patient survival improves non-significantly. Axl is an essential regulator in cancer metastasis and patient survival. In this study, we developed a controlled-release polyanhydride polymer loading a novel small molecule, n-butylidenephthalide (BP), which is not only increasing local drug concentration and extending its diffusion distance but also reducing tumour invasion, mediated by reducing Axl expression. First, we determined that BP inhibited the expression of Axl in a dose- and time-dependent manner and reduced the migratory and invasive capabilities of GBM cells. In addition, BP downregulated matrix metalloproteinase activity, which is involved in cancer cell invasion. Furthermore, we demonstrated that BP regulated Axl via the extracellular signal-regulated kinases pathway. Epithelial-to-mesenchymal transition (EMT) is related to epithelial cells in the invasive migratory mesenchymal cells that underlie cancer progression; we demonstrated that BP reduced the expression of EMT-related genes. Furthermore, we used the overexpression of Axl in GBM cells to prove that Axl is a crucial target in the inhibition of GBM EMT, migration and invasion. In an in vivo study, we demonstrated that BP inhibited tumour growth and suppressed Axl expression in a dose-dependent manner according to a subcutaneous tumour model. Most importantly, in an intracranial tumour model with BP wafer in situ treatment, we demonstrated that the BP wafer not only significantly increased the survival rate but also decreased Axl expression, and inhibited tumour invasion. These results contribute to the

  9. Gold Nanoparticle–Mediated Targeted Delivery of Recombinant Human Endostatin Normalizes Tumour Vasculature and Improves Cancer Therapy

    PubMed Central

    Li, Wei; Zhao, Xiaoxu; Du, Bin; Li, Xin; Liu, Shuhao; Yang, Xiao-Yan; Ding, Hui; Yang, Wende; Pan, Fan; Wu, Xiaobo; Qin, Li; Pan, Yunlong

    2016-01-01

    Tumour vasculature is generally disordered because of the production of excessive angiogenic factors by tumour cells, which results in tumour progression and reduces the effectiveness of radiotherapy or chemotherapy. Transient anti-angiogenic therapies that regulate tumour vascular morphology and function and improve the efficiency of antitumour therapy are under investigation. Recombinant human endostatin (Endostar/rhES) is a vascular angiogenesis–disrupting agent that has been used to treat non-small cell lung cancer (NSCLC) in the clinical setting. In this study, we used gold nanoparticles (AuNPs) as a drug-delivery system (DDS) for targeted tumour delivery of rhES for short therapy, which resulted in transient tumour vascular normalization, reduced permeability and hypoxia, strengthened blood vessel integrity, and increased blood-flow perfusion. Moreover, combination therapy with 5-FU over this timeframe was substantially more effective than 5-FU monotherapy. In conclusion, our research demonstrates the potential use of AuNPs as a drug-delivery platform for transporting rhES into a tumour to induce transient tumour vascular normalization and enhance the antitumour efficacy of cytotoxic drugs. PMID:27470938

  10. Melanosomes foster a tumour niche by activating CAFs.

    PubMed

    García-Silva, Susana; Peinado, Héctor

    2016-08-30

    Extracellular vesicles, such as exosomes, are important effectors in the formation of tumour-fostering niches. Pigmented melanosomes are now shown to have a relevant role in establishing a tumour niche in primary melanoma by reprogramming dermal fibroblasts into cancer-associated fibroblasts through the transfer of miR-211. PMID:27571736

  11. Increased midkine expression correlates with desmoid tumour recurrence: a potential biomarker and therapeutic target.

    PubMed

    Colombo, Chiara; Creighton, Chad J; Ghadimi, Markus P; Bolshakov, Svetlana; Warneke, Carla L; Zhang, Yiqun; Lusby, Kristelle; Zhu, Shirley; Lazar, Alexander J; West, Robert B; van de Rijn, Matt; Lev, Dina

    2011-12-01

    Desmoid tumours (DTs) are soft tissue monoclonal neoplasms exhibiting a unique phenotype, consisting of aggressive local invasiveness without metastatic capacity. While DTs can infrequently occur as part of familial adenomatosis polyposis, most cases arise sporadically. Sporadic DTs harbour a high prevalence of CTNNB1 mutations and hence increased β-catenin signalling. However, β-catenin downstream transcriptional targets and other molecular deregulations operative in DT inception and progression are currently not well defined, contributing to the lack of sensitive molecular prognosticators and efficacious targeted therapeutic strategies. We compared the gene expression profiles of 14 sporadic DTs to those of five corresponding normal tissues and six solitary fibrous tumour specimens. A DT expression signature consisting of 636 up- and 119 down-regulated genes highly enriched for extracellular matrix, cell adhesion and wound healing-related proteins was generated. Furthermore, 98 (15%) of the over-expressed genes were demonstrated to contain a TCF/LEF consensus binding site in their promoters, possibly heralding direct β-catenin downstream targets relevant to DT. The protein products of three of the up-regulated DT genes: ADAM12, MMP2 and midkine, were found to be commonly expressed in a large cohort of human DT samples assembled on a tissue microarray. Interestingly, enhanced midkine expression significantly correlated with a higher propensity and decreased time for primary DT recurrence (log-rank p = 0.0025). Finally, midkine was found to enhance the migration and invasion of primary DT cell cultures. Taken together, these studies provide insights into potential DT molecular aberrations and novel β-catenin transcriptional targets. Further studies to confirm the utility of midkine as a clinical DT molecular prognosticator and a potential therapeutic target are therefore warranted. Raw gene array data can be found at: http://smd.stanford.edu/ PMID:21826666

  12. CDK1 Is a Synthetic Lethal Target for KRAS Mutant Tumours

    PubMed Central

    Costa-Cabral, Sara; Brough, Rachel; Konde, Asha; Aarts, Marieke; Campbell, James; Marinari, Eliana; Riffell, Jenna; Bardelli, Alberto; Torrance, Christopher; Lord, Christopher J.; Ashworth, Alan

    2016-01-01

    Activating KRAS mutations are found in approximately 20% of human cancers but no RAS-directed therapies are currently available. Here we describe a novel, robust, KRAS synthetic lethal interaction with the cyclin dependent kinase, CDK1. This was discovered using parallel siRNA screens in KRAS mutant and wild type colorectal isogenic tumour cells and subsequently validated in a genetically diverse panel of 26 colorectal and pancreatic tumour cell models. This established that the KRAS/CDK1 synthetic lethality applies in tumour cells with either amino acid position 12 (p.G12V, pG12D, p.G12S) or amino acid position 13 (p.G13D) KRAS mutations and can also be replicated in vivo in a xenograft model using a small molecule CDK1 inhibitor. Mechanistically, CDK1 inhibition caused a reduction in the S-phase fraction of KRAS mutant cells, an effect also characterised by modulation of Rb, a master control of the G1/S checkpoint. Taken together, these observations suggest that the KRAS/CDK1 interaction is a robust synthetic lethal effect worthy of further investigation. PMID:26881434

  13. Human monoclonal antibodies targeting carbonic anhydrase IX for the molecular imaging of hypoxic regions in solid tumours

    PubMed Central

    Ahlskog, J K J; Schliemann, C; Mårlind, J; Qureshi, U; Ammar, A; Pedley, R B; Neri, D

    2009-01-01

    Background: Hypoxia, which is commonly observed in areas of primary tumours and of metastases, influences response to treatment. However, its characterisation has so far mainly been restricted to the ex vivo analysis of tumour sections using monoclonal antibodies specific to carbonic anhydrase IX (CA IX) or by pimonidazole staining, after the intravenous administration of this 2-nitroimidazole compound in experimental animal models. Methods: In this study, we describe the generation of high-affinity human monoclonal antibodies (A3 and CC7) specific to human CA IX, using phage technology. Results: These antibodies were able to stain CA IX ex vivo and to target the cognate antigen in vivo. In one of the two animal models of colorectal cancer studied (LS174T), CA IX imaging closely matched pimonidazole staining, with a preferential staining of tumour areas characterised by little vascularity and low perfusion. In contrast, in a second animal model (SW1222), distinct staining patterns were observed for pimonidazole and CA IX targeting. We observed a complementary pattern of tumour regions targeted in vivo by the clinical-stage vascular-targeting antibody L19 and the anti-CA IX antibody A3, indicating that a homogenous pattern of in vivo tumour targeting could be achieved by a combination of the two antibodies. Conclusion: The new human anti-CA IX antibodies are expected to be non-immunogenic in patients with cancer and may serve as broadly applicable reagents for the non-invasive imaging of hypoxia and for pharmacodelivery applications. PMID:19623173

  14. New sorafenib derivatives: synthesis, antiproliferative activity against tumour cell lines and antimetabolic evaluation.

    PubMed

    Babić, Zeljka; Crkvenčić, Maja; Rajić, Zrinka; Mikecin, Ana-Matea; Kralj, Marijeta; Balzarini, Jan; Petrova, Mariya; Vanderleyden, Jos; Zorc, Branka

    2012-01-01

    Sorafenib is a relatively new cytostatic drug approved for the treatment of renal cell and hepatocellular carcinoma. In this report we describe the synthesis of sorafenib derivatives 4a-e which differ from sorafenib in their amide part. A 4-step synthetic pathway includes preparation of 4-chloropyridine-2-carbonyl chloride hydrochloride (1), 4-chloro-pyridine-2-carboxamides 2a-e, 4-(4-aminophenoxy)-pyridine-2-carboxamides 3a-e and the target compounds 4-[4-[[4-chloro-3-(trifluoromethyl)phenyl]carbamoylamino]-phenoxy]-pyridine-2-carboxamides 4a-e. All compounds were fully chemically characterized and evaluated for their cytostatic activity against a panel of carcinoma, lymphoma and leukemia tumour cell lines. In addition, their antimetabolic potential was investigated as well. The most prominent antiproliferative activity was obtained for compounds 4a-e (IC(50) = 1-4.3 μmol·L-1). Their potency was comparable to the potency of sorafenib, or even better. The compounds inhibited DNA, RNA and protein synthesis to a similar extent and did not discriminate between tumour cell lines and primary fibroblasts in terms of their anti-proliferative activity. PMID:22269830

  15. A preliminary investigation of the role of the transcription co-activators YAP/TAZ of the Hippo signalling pathway in canine and feline mammary tumours.

    PubMed

    Beffagna, G; Sacchetto, R; Cavicchioli, L; Sammarco, A; Mainenti, M; Ferro, S; Trez, D; Zulpo, M; Michieletto, S; Cecchinato, A; Goldschmidt, M; Zappulli, V

    2016-01-01

    Breast cancer is the most common cancer in women worldwide. Cancer metastases are responsible for the high mortality rate. A small but distinct subset of cells, cancer stem cells (CSCs), have the capacity to self-renew, initiate tumour formation, and develop metastases. The CSC content in human breast cancer correlates with the Hippo tumour suppressor signalling pathway. Specifically, the activity of YAP/TAZ, transcription co-activators of the Hippo pathway, sustains the self-renewal and tumour-initiation capacities of CSCs. Little is known about YAP/TAZ in canine and feline mammary tumours, which are very common tumours. The preliminary aim of the study was to investigate the expression of YAP/TAZ in canine and feline mammary tumours by Western blot and immunohistochemistry. Increased cytoplasmic and nuclear expression of YAP/TAZ was observed in all carcinomas compared to normal tissues, indicating neoplastic deregulation of the Hippo pathway. Nuclear expression significantly increased in grade III (high grade carcinomas) compared to grade I (low grade carcinomas) tumours, suggesting that YAP/TAZ play a role in the increased aggressiveness of these tumours. Moreover, different scoring systems for immunohistochemical analyses were compared and the H index and the Allred scores were the most significant. In conclusion, YAP/TAZ are expressed in aggressive canine and feline mammary tumours as reported in some human cancers. Further studies might better elucidate the role of the Hippo pathway in prognosis and as a target for new therapies. In addition, tumours in dogs and cats may be a useful model to study this pathway. PMID:26626094

  16. Localization of sunitinib, its metabolites and its target receptors in tumour-bearing mice: a MALDI-MS imaging study

    PubMed Central

    Torok, S; Vegvari, A; Rezeli, M; Fehniger, T E; Tovari, J; Paku, S; Laszlo, V; Hegedus, B; Rozsas, A; Dome, B; Marko-Varga, G

    2015-01-01

    Background and Purpose The clinical effects of anti-angiogenic agents remain controversial. Therefore, elucidating the pharmacological properties of these compounds is a pivotal issue. Experimental Approach The effects of treatment with sunitinib on tumour and normal tissues of mice bearing C-26 adenocarcinoma cells were analysed by matrix-assisted laser desorption ionization MS imaging (MALDI-MSI). Expression of the key targets of sunitinib – angiogenic receptors – was studied by immunofluorescent labelling. Key Results MALDI-MS assays showed that sunitinib and its fragment ions were present throughout tumour and normal tissues. Major metabolites were identified in blood and solid tissues, while minor drug metabolites were detectable only in blood. Tumour growth and intratumour VEGF receptor-2 expressions were significantly reduced in sunitinib-treated mice, while the expression of the other targeted receptors, PDGF receptor -α or -β and fibroblast growth factor receptor-1, remained unaffected. Within tumour tissue, the close proximity of sunitinib metabolites to the precursor ion suggested in situ metabolism of the administered drug. There were intratumour areas where the signal intensity of sunitinib correlated with expression of VEGF receptor-2. Conclusions and Implications This is the first study that demonstrates MALDI-MSI is a versatile platform to study the intratumour localization of an unlabelled anti-angiogenic drug. The combination of MALDI-MSI and immunofluorescence analysis can provide further insights into the molecular interaction of drug compounds and their targets within tumour tissue. PMID:25363319

  17. Influence of tumour condition on the macrophage activity in Candida albicans infection.

    PubMed

    Venturini, J; de Camargo, M R; Félix, M C; Vilani-Moreno, F R; de Arruda, M S P

    2009-07-01

    To better understand the interactions between opportunistic fungi and their hosts, we investigated hydrogen peroxide (H2O2), nitric oxide and TNF-alpha production by peritoneal macrophages from Ehrlich tumour-bearing mice (TBM) during microbial infections. For this purpose, TBM at days 7, 14 and 21 of tumour progression were inoculated intraperitoneally with C. albicans and evaluated after 24 and 72 h. We observed that TBM showed significant increases in H2O2, TNF-alpha levels and fungal clearance at day 7 after C. albicans infection. However, as the tumour advanced, there was a progressive decline in the release of H2O2 and TNF-alpha that was paired with the dissemination of C. albicans. These results demonstrate that protective macrophage activities against Candida albicans are limited to the initial stages of tumour growth; continued solid tumour growth weakened the macrophage response and as a consequence, weakened the host's susceptibility to opportunistic infections. PMID:19522762

  18. Suppression of microRNA activity amplifies IFN-γ-induced macrophage activation and promotes anti-tumour immunity.

    PubMed

    Baer, Caroline; Squadrito, Mario Leonardo; Laoui, Damya; Thompson, Danielle; Hansen, Sarah K; Kiialainen, Anna; Hoves, Sabine; Ries, Carola H; Ooi, Chia-Huey; De Palma, Michele

    2016-07-01

    Tumour-associated macrophages (TAMs) largely express an alternatively activated (or M2) phenotype, which entails immunosuppressive and tumour-promoting capabilities. Reprogramming TAMs towards a classically activated (M1) phenotype may thwart tumour-associated immunosuppression and unleash anti-tumour immunity. Here we show that conditional deletion of the microRNA (miRNA)-processing enzyme DICER in macrophages prompts M1-like TAM programming, characterized by hyperactive IFN-γ/STAT1 signalling. This rewiring abated the immunosuppressive capacity of TAMs and fostered the recruitment of activated cytotoxic T lymphocytes (CTLs) to the tumours. CTL-derived IFN-γ exacerbated M1 polarization of Dicer1-deficient TAMs and inhibited tumour growth. Remarkably, DICER deficiency in TAMs negated the anti-tumoral effects of macrophage depletion by anti-CSF1R antibodies, and enabled complete tumour eradication by PD1 checkpoint blockade or CD40 agonistic antibodies. Finally, genetic rescue of Let-7 miRNA activity in Dicer1-deficient TAMs partly restored their M2-like phenotype and decreased tumour-infiltrating CTLs. These findings suggest that DICER/Let-7 activity opposes IFN-γ-induced, immunostimulatory M1-like TAM activation, with potential therapeutic implications. PMID:27295554

  19. Anti-tumour/metastasis effects of the potassium-sparing diuretic amiloride: an orally active anti-cancer drug waiting for its call-of-duty?

    PubMed

    Matthews, Hayden; Ranson, Marie; Kelso, Michael J

    2011-11-01

    Amiloride.HCl is clinically used as an oral potassium-sparing diuretic, but multiple studies in biochemical, cellular and animal models have shown that the drug also possesses anti-tumour and anti-metastasis activities. The additional effects appear to arise through inhibition of two discrete targets: (i) the sodium-hydrogen exchanger 1 (NHE1), a membrane protein responsible for the characteristically low extracellular pH of tumours and (ii) the urokinase-type plasminogen activator (uPA), a serine protease mediator of cell migration, invasion and metastasis and well-known marker of poor prognosis in cancer. This mini-review summarises for the first time the reported anti-tumour/metastasis effects of amiloride in experimental models, discusses the putative molecular mechanisms responsible for these effects and concludes by commenting on the pros and cons of trialling amiloride or one of its structural analogues as potential new anti-tumour/metastasis drugs. PMID:21544803

  20. Induction of DT-diaphorase by 1,2-dithiole-3-thiones in human tumour and normal cells and effect on anti-tumour activity of bioreductive agents.

    PubMed Central

    Doherty, G. P.; Leith, M. K.; Wang, X.; Curphey, T. J.; Begleiter, A.

    1998-01-01

    DT-diaphorase is a two-electron-reducing enzyme that is an important activator of bioreductive anti-tumour agents, such as mitomycin C (MMC) and EO9, and is inducible by many compounds, including 1,2-dithiole-3-thiones (D3Ts). We showed previously that D3T selectively increased DT-diaphorase activity in mouse lymphoma cells compared with normal mouse marrow cells, and also increased MMC or EO9 cytotoxic activity in the lymphoma cells with only minor effects in the marrow cells. In this study, we found that D3T significantly increased DT-diaphorase activity in 28 of 38 human tumour cell lines representing ten tissue types with no obvious relationships between the tumour type, or the base level of DT-diaphorase activity, and the ability of D3T to increase the enzyme activity. Induction of DT-diaphorase activity in human tumour cell lines by 12 D3T analogues varied markedly with the D3T structure. D3T also increased DT-diaphorase activity in normal human bone marrow and kidney cells but the increases were small in these cells. In addition, D3T increased the level of enzyme activity in normal human lung cells. Pretreatment of human tumour cells with D3T analogues significantly increased the cytotoxic activity of MMC or EO9 in these cells, and the level of enhancement of anti-tumour activity paralleled the level of DT-diaphorase induction. In contrast, D3T did not effect the toxicity of EO9 in normal kidney cells. These results demonstrate that D3T analogues can increase DT-diaphorase activity in a wide variety of human tumour cells and that this effect can enhance the anti-tumour activity of the bioreductive agents MMC and EO9. PMID:9579829

  1. Selective targeting of tumour neovasculature by a radiohalogenated human antibody fragment specific for the ED-B domain of fibronectin.

    PubMed

    Demartis, S; Tarli, L; Borsi, L; Zardi, L; Neri, D

    2001-04-01

    Angiogenesis is a characteristic feature of many aggressive tumours and other disorders. Antibodies capable of binding to new blood vessels, but not to mature vessels, could be used as selective targeting agents for immunoscintigraphic and radioimmunotherapeutic applications. Here we show that scFv(L19), a recombinant human antibody fragment with sub-nanomolar affinity for the ED-B domain of fibronectin, a marker of angiogenesis, can be stably labelled with iodine-125 and astatine-211 with full retention of immunoreactivity, using a trimethyl-stannyl benzoate bifunctional derivative. Biodistribution studies in mice bearing two different types of tumour grafted subcutaneously, followed by ex vivo micro-autoradiographic analysis, revealed that scFv(L19) rapidly localises around tumour blood vessels, but not around normal vessels. Four hours after intravenous injection of the stably radioiodinated scFv(L19), tumour to blood ratios were 6:1 in mice bearing the F9 murine teratocarcinoma and 9:1 in mice bearing an FE8 rat sarcoma. As expected, all other organs (including kidney) contained significantly less radioactivity than the tumour. Since the ED-B domain of fibronectin has an identical sequence in mouse and man, scFv(L19) is a pan-species antibody and the results presented here suggest clinical utility of radiolabelled scFv(L19) for the scintigraphic detection of angiogenesis in vivo. Furthermore, it should now be possible to investigate scFv(L19) for the selective delivery of 211At to the tumour neovasculature, causing the selective death of tumour endothelial cells and tumour collapse. PMID:11357506

  2. LAT1 targeted delivery of methionine based imaging probe derived from M(III) metal ions for early diagnosis of proliferating tumours using molecular imaging modalities.

    PubMed

    Hazari, Puja Panwar; Prakash, Surbhi; Meena, Virendra K; Jaswal, Ambika; Khurana, Harleen; Mishra, Surabhi Kirti; Bhonsle, Hemanth Kumar; Singh, Lokendra; Mishra, Anil K

    2015-01-01

    We investigated the potential of DTPA-bis(Methionine), a target specific amino acid based probe for detection of L-type amino acid transporters (LAT1) known to over express in proliferating tumours using multimodality imaging. The ligand, DTPA-bis(Met) was readily converted to lanthanide complexes and was found capable of targeting cancer cells using multimodality imaging. DTPA-bis(Met) complexes were synthesized and characterized by mass spectroscopy. MR longitudinal relaxivity, r₁ = 4.067 ± 0.31 mM⁻¹s⁻¹ and transverse relaxivity, r₂ = 8.61 ± 0.07 mM⁻¹s⁻¹ of Gd(III)-DTPA-bis(Met) were observed at pH 7.4 at 7 T. Bright, localized fluorescence of Eu(III)-DTPA-bis(Met) was observed with standard microscopy and displacement studies indicated ligand functionality. K(D) value determined for Eu(III)-DTPA-bis(Met) on U-87 MG cells was found to be 17.3 pM and showed appreciable fluorescence within the cells. Radio HPLC showed a radiochemical purity more than 95% (specific activity = 400-500 MBq/μmol, labelling efficiency 78 %) for ⁶⁸Ga(III)-DTPA-bis(Met). Pre-treatment of xenografted U-87 MG athymic mice with ⁶⁸Ga(III)-DTPA-bis(Met) following unlabelled L-methionine administration reduced tumour uptake by 10-folds in Micro PET. These data support the specific binding of ⁶⁸Ga(III)-DTPA-bis(Met) to the LAT1 transporter. To summarize, this agent possesses high stability in biological environment and exhibits effective interaction with its LAT1 transporters giving high accumulation in tumour area, excellent tumour/non-tumour ratio and low non-specific retention in vivo. PMID:25329672

  3. Interaction of thalidomide, phthalimide analogues of thalidomide and pentoxifylline with the anti-tumour agent 5,6-dimethylxanthenone-4-acetic acid: concomitant reduction of serum tumour necrosis factor-alpha and enhancement of anti-tumour activity.

    PubMed Central

    Ching, L. M.; Browne, W. L.; Tchernegovski, R.; Gregory, T.; Baguley, B. C.; Palmer, B. D.

    1998-01-01

    DMXAA (5,6-dimethylxanthenone-4-acetic acid), a novel anti-tumour agent currently undergoing clinical evaluation, appears to mediate its anti-tumour effects through immune modulation and the production of the cytokine tumour necrosis factor-alpha (TNF). Our previous studies have shown that thalidomide, a potent inhibitor of TNF biosynthesis that has numerous biological effects, including inhibition of tumour angiogenesis, unexpectedly augments the anti-tumour response in mice to DMXAA. We show here that thalidomide (100 mg kg(-1)) has no effect when administered with inactive doses of DMXAA, and that it must be given simultaneously with an active dose of DMXAA to have its maximum potentiating effect on the growth of the murine Colon 38 adenocarcinoma. To address the issue of whether inhibition of serum TNF production is important for potentiation of anti-tumour activity, we have tested three potent analogues of thalidomide. All three analogues, when co-administered with DMXAA to mice at doses lower than those used with thalidomide, inhibited TNF production and were effective in potentiating the anti-tumour activity of DMXAA against transplanted Colon 38 tumours. One of the analogues, N-phenethyltetrafluorophthalimide, was 1000-fold more potent than thalidomide and at a dose of 0.1 mg kg(-1) in combination with DMXAA (30 mg kg(-1)) cured 100% of mice, compared with 67% for the group treated with DMXAA alone. We also tested pentoxifylline and found it to suppress TNF production in response to DMXAA and to potentiate the anti-tumour effect of DMXAA. The results are compatible with the hypothesis that pharmacological reduction of serum TNF levels might benefit the anti-tumour effects of DMXAA and suggest new strategies for therapy using this agent. PMID:9703279

  4. Tumour necrosis factor (TNFα) as a novel therapeutic target in symptomatic corticosteroid dependent asthma

    PubMed Central

    Howarth, P; Babu, K; Arshad, H; Lau, L; Buckley, M; McConnell, W; Beckett, P; Al, A; Chauhan, A; Wilson, S; Reynolds, A; Davies, D; Holgate, S

    2005-01-01

    Background: Tumour necrosis factor α (TNFα) is a major therapeutic target in a range of chronic inflammatory disorders characterised by a Th1 type immune response in which TNFα is generated in excess. By contrast, asthma is regarded as a Th2 type disorder, especially when associated with atopy. However, as asthma becomes more severe and chronic, it adopts additional characteristics including corticosteroid refractoriness and involvement of neutrophils suggestive of an altered inflammatory profile towards a Th1 type response, incriminating cytokines such as TNFα. Methods: TNFα levels in bronchoalveolar lavage (BAL) fluid of 26 healthy controls, 42 subjects with mild asthma and 20 with severe asthma were measured by immunoassay, and TNFα gene expression was determined in endobronchial biopsy specimens from 14 patients with mild asthma and 14 with severe asthma. The cellular localisation of TNFα was assessed by immunohistochemistry. An open label uncontrolled clinical study was then undertaken in 17 subjects with severe asthma to evaluate the effect of 12 weeks of treatment with the soluble TNFα receptor-IgG1Fc fusion protein, etanercept. Results: TNFα levels in BAL fluid, TNFα gene expression and TNFα immunoreative cells were increased in subjects with severe corticosteroid dependent asthma. Etanercept treatment was associated with improvement in asthma symptoms, lung function, and bronchial hyperresponsiveness. Conclusions: These findings may be of clinical significance in identifying TNFα as a new therapeutic target in subjects with severe asthma. The effects of anti-TNF treatment now require confirmation in placebo controlled studies. PMID:16166100

  5. Plasminogen Activator of the Blood Vessels in Tumours and in Carrageenin-induced Granulomas

    PubMed Central

    Pick, C. R.; Cater, D. B.

    1971-01-01

    Fibrinolytic activity in tumours was studied by the fibrin slide technique. The tumour cells were inactive and fibrinolysis was seen only in areas with young blood vessels. In carrageenin-induced granulomas at 6 days the fibrinolytic activity was small and confined to mature veins, but from 7-14 days activity was high in zones containing young vessels supplying the terminal capillary buds; these latter showed no activity. In old fibrosed granulomas there was no fibrinolytic activity. The vascular permeability changes of inflammation (detected by the colloidal carbon technique) showed no correlation with fibrinolytic activity, and systemic injection of inflammatory agents had no effect on the fibrinolytic activity of the vessels. These findings are discussed in relationship to tumour vascularization. ImagesFigs. 5-8Figs. 1-4 PMID:5547651

  6. Targeting of small molecule anticancer drugs to the tumour and its vasculature using cationic liposomes: lessons from gene therapy

    PubMed Central

    Dass, Crispin R; Choong, Peter FM

    2006-01-01

    Cationic (positively charged) liposomes have been tested in various gene therapy clinical trials for neoplastic and other diseases. They have demonstrated selectivity for tumour vascular endothelial cells raising hopes for both antiangiogenic and antivascular therapies. They are also capable of being selectively delivered to the lungs and liver when administered intravenously. These vesicles are being targeted to the tumour in various parts of the body by using advanced liposomal systems such as ligand-receptor and antibody-antigen combinations. At present, the transferrin receptor is commonly used for cancer-targeted drug delivery systems including cationic liposomes. This review looks at the growing utility of these vesicles for delivery of small molecule anticancer drugs. PMID:16792817

  7. Which alkylglycerols from shark liver oil have anti-tumour activities?

    PubMed

    Deniau, Anne-Laure; Mosset, Paul; Le Bot, Damien; Legrand, Alain B

    2011-01-01

    Alkylglycerols (alkyl-Gro) are ether lipids abundant in shark liver oil (SLO), and oral SLO or alkyl-Gro mix from this source have several in vivo biological activities including stimulation of haematopoiesis an immunological defences, or anti-tumour and anti-metastasis activities in vivo. Composition of natural alkyl-Gro mix contains several alkyl-Gro varying by chain length and unsaturation, and individual anti-tumour activity of each molecule present in natural mix remained unknown. We synthesized 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. Using an in vivo model of grafted tumour in mice (3LL cells), we studied and compared the oral anti-tumour and anti-metastasis activities of each of these 6 alkyl-Gro. 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. Spleen weights at day 20 after graft were also measured and showed tremendous variations depending on the treatment. Tumour graft resulted in a raise in spleen weight in control group, this raise was nearly abolished in 16:1 and 18:1 alkyl-Gro-treated mice, and was reduced in 14:0 and 16:0 alkyl-Gro-treated mice. Conversely, 18:0 alkyl-Gro-treated mice showed spleen weigh raise as compared with untreated grafted mice. These new data demonstrate a prominent role of unsaturation in the anti-tumour activities of alkyl-Gro. PMID:20036307

  8. Exploiting developments in nanotechnology for the preferential delivery of platinum-based anti-cancer agents to tumours: targeting some of the hallmarks of cancer.

    PubMed

    Parker, James P; Ude, Ziga; Marmion, Celine J

    2016-01-01

    Platinum drugs as anti-cancer therapeutics are held in extremely high regard. Despite their success, there are drawbacks associated with their use; their dose-limiting toxicity, their limited activity against an array of common cancers and patient resistance to Pt-based therapeutic regimes. Current investigations in medicinal inorganic chemistry strive to offset these shortcomings through selective targeting of Pt drugs and/or the development of Pt drugs with new or multiple modes of action. A comprehensive overview showcasing how liposomes, nanocapsules, polymers, dendrimers, nanoparticles and nanotubes may be employed as vehicles to selectively deliver cytotoxic Pt payloads to tumour cells is provided. PMID:26567482

  9. Activation of multiple chemotherapeutic prodrugs by the natural enzymolome of tumour-localised probiotic bacteria.

    PubMed

    Lehouritis, Panos; Stanton, Michael; McCarthy, Florence O; Jeavons, Matthieu; Tangney, Mark

    2016-01-28

    Some chemotherapeutic drugs (prodrugs) require activation by an enzyme for efficacy. We and others have demonstrated the ability of probiotic bacteria to grow specifically within solid tumours following systemic administration, and we hypothesised that the natural enzymatic activity of these tumour-localised bacteria may be suitable for activation of certain such chemotherapeutic drugs. Several wild-type probiotic bacteria; Escherichia coli Nissle, Bifidobacterium breve, Lactococcus lactis and Lactobacillus species, were screened against a panel of popular prodrugs. All strains were capable of activating at least one prodrug. E. coli Nissle 1917 was selected for further studies because of its ability to activate numerous prodrugs and its resistance to prodrug toxicity. HPLC data confirmed biochemical transformation of prodrugs to their toxic counterparts. Further analysis demonstrated that different enzymes can complement prodrug activation, while simultaneous activation of multiple prodrugs (CB1954, 5-FC, AQ4N and Fludarabine phosphate) by E. coli was confirmed, resulting in significant efficacy improvement. Experiments in mice harbouring murine tumours validated in vitro findings, with significant reduction in tumour growth and increase in survival of mice treated with probiotic bacteria and a combination of prodrugs. These findings demonstrate the ability of probiotic bacteria, without the requirement for genetic modification, to enable high-level activation of multiple prodrugs specifically at the site of action. PMID:26655063

  10. Targeted inhibition of the deubiquitinating enzymes, USP14 and UCHL5, induces proteotoxic stress and apoptosis in Waldenström macroglobulinaemia tumour cells

    PubMed Central

    Chitta, Kasyapa; Paulus, Aneel; Akhtar, Sharoon; Blake, Maja Kristin K.; Caulfield, Thomas R.; Novak, Anne J.; Ansell, Stephen M.; Advani, Pooja; Ailawadhi, Sikander; Sher, Taimur; Linder, Stig; Chanan-Khan, Asher

    2016-01-01

    Summary Deubiquitinase enzymes (DUBs) of the proteasomal 19S regulatory particle are emerging as important therapeutic targets in several malignancies. Here we demonstrate that inhibition of two proteasome-associated DUBs (USP14 and UCHL5) with the small molecule DUB inhibitor b-AP15, results in apoptosis of human Waldenström macroglobulinaemia (WM) cell lines and primary patient-derived WM tumour cells. Importantly, b-AP15 produced proteotoxic stress and apoptosis in WM cells that have acquired resistance to the proteasome inhibitor bortezomib. In silico modelling identified protein residues that were critical for the binding of b-AP15 with USP14 or UCHL5 and proteasome enzyme activity assays confirmed that b-AP15 does not affect the proteolytic capabilities of the 20S proteasome β-subunits. In vitro toxicity from b-AP15 appeared to result from a build-up of ubiquitinated proteins and activation of the endoplasmic reticulum stress response in WM cells, an effect that also disrupted the mitochondria. Focused transcriptome profiling of b-AP15-treated WM cells revealed modulation of several genes regulating cell stress and NF-κB signalling, the latter whose protein translocation and downstream target activation was reduced by b-AP15 in vitro. This is the first report to define the effects and underlying mechanisms associated with inhibition of USP14 and UCHL5 DUB activity in WM tumour cells. PMID:25691154

  11. PBX3 is targeted by multiple miRNAs and is essential for liver tumour-initiating cells.

    PubMed

    Han, Haibo; Du, Yantao; Zhao, Wei; Li, Sheng; Chen, Dongji; Zhang, Jing; Liu, Jiang; Suo, Zhenhe; Bian, Xiuwu; Xing, Baocai; Zhang, Zhiqian

    2015-01-01

    Tumour-initiating cells (TICs) are advocated to constitute the sustaining force to maintain and renew fully established malignancy; however, the molecular mechanisms responsible for these properties are elusive. We previously demonstrated that voltage-gated calcium channel α2δ1 subunit marks hepatocellular carcinoma (HCC) TICs. Here we confirm directly that α2δ1 is a HCC TIC surface marker, and identify let-7c, miR-200b, miR-222 and miR-424 as suppressors of α2δ1(+) HCC TICs. Interestingly, all the four miRNAs synergistically target PBX3, which is sufficient and necessary for the acquisition and maintenance of TIC properties. Moreover, PBX3 drives an essential transcriptional programme, activating the expression of genes critical for HCC TIC stemness including CACNA2D1, EpCAM, SOX2 and NOTCH3. In addition, the expression of CACNA2D1 and PBX3 mRNA is predictive of poor prognosis for HCC patients. Collectively, our study identifies an essential signalling pathway that controls the switch of HCC TIC phenotypes. PMID:26420065

  12. XRP44X, an Inhibitor of Ras/Erk Activation of the Transcription Factor Elk3, Inhibits Tumour Growth and Metastasis in Mice.

    PubMed

    Semenchenko, Kostyantyn; Wasylyk, Christine; Cheung, Henry; Tourrette, Yves; Maas, Peter; Schalken, Jack A; van der Pluijm, Gabri; Wasylyk, Bohdan

    2016-01-01

    Transcription factors have an important role in cancer but are difficult targets for the development of tumour therapies. These factors include the Ets family, and in this study Elk3 that is activated by Ras oncogene /Erk signalling, and is involved in angiogenesis, malignant progression and epithelial-mesenchymal type processes. We previously described the identification and in-vitro characterisation of an inhibitor of Ras / Erk activation of Elk3 that also affects microtubules, XRP44X. We now report an initial characterisation of the effects of XRP44X in-vivo on tumour growth and metastasis in three preclinical models mouse models, subcutaneous xenografts, intra-cardiac injection-bone metastasis and the TRAMP transgenic mouse model of prostate cancer progression. XRP44X inhibits tumour growth and metastasis, with limited toxicity. Tumours from XRP44X-treated animals have decreased expression of genes containing Elk3-like binding motifs in their promoters, Elk3 protein and phosphorylated Elk3, suggesting that perhaps XRP44X acts in part by inhibiting the activity of Elk3. Further studies are now warranted to develop XRP44X for tumour therapy. PMID:27427904

  13. XRP44X, an Inhibitor of Ras/Erk Activation of the Transcription Factor Elk3, Inhibits Tumour Growth and Metastasis in Mice

    PubMed Central

    Cheung, Henry; Tourrette, Yves; Maas, Peter; Schalken, Jack A; van der Pluijm, Gabri

    2016-01-01

    Transcription factors have an important role in cancer but are difficult targets for the development of tumour therapies. These factors include the Ets family, and in this study Elk3 that is activated by Ras oncogene /Erk signalling, and is involved in angiogenesis, malignant progression and epithelial-mesenchymal type processes. We previously described the identification and in-vitro characterisation of an inhibitor of Ras / Erk activation of Elk3 that also affects microtubules, XRP44X. We now report an initial characterisation of the effects of XRP44X in-vivo on tumour growth and metastasis in three preclinical models mouse models, subcutaneous xenografts, intra-cardiac injection-bone metastasis and the TRAMP transgenic mouse model of prostate cancer progression. XRP44X inhibits tumour growth and metastasis, with limited toxicity. Tumours from XRP44X-treated animals have decreased expression of genes containing Elk3-like binding motifs in their promoters, Elk3 protein and phosphorylated Elk3, suggesting that perhaps XRP44X acts in part by inhibiting the activity of Elk3. Further studies are now warranted to develop XRP44X for tumour therapy. PMID:27427904

  14. ΔPK oncolytic activity includes modulation of the tumour cell milieu.

    PubMed

    Bollino, Dominique; Colunga, Aric; Li, Baiquan; Aurelian, Laure

    2016-02-01

    Oncolytic virotherapy is a unique cancer therapeutic that encompasses tumour cell lysis through both virus replication and programmed cell death (PCD) pathways. Nonetheless, clinical efficacy is relatively modest, likely related to the immunosuppressive tumour milieu. Our studies use the herpes simplex virus type 2 (HSV-2)-based oncolytic virus ΔPK that has documented anti-tumour activity associated with virus replication, PCD and cancer stem cell lysis. They are designed to examine whether ΔPK-mediated oncolysis includes the ability to reverse the immunosuppressive tumour microenvironment by altering the balance of cytokines directly secreted by the melanoma cells and to define its mechanism. Here, we show that melanoma cells secreted the immunosuppressive cytokine IL-10, and that secretion was inhibited by ΔPK through virus replication and c-Jun N-terminal kinase/c-Jun activation. ΔPK-induced IL-10 inhibition upregulated surface expression of MHC class I chain-related protein A, the ligand for the activating NKG2D receptor expressed on NK- and cytotoxic T-cells. Concomitantly, ΔPK also upregulated the secretion of inflammatory cytokines TNF-α, granulocyte macrophage colony-stimulating factor and IL-1β through autophagy-mediated activation of Toll-like receptor 2 pathways and pyroptosis, and it inhibited the expression of the negative immune checkpoint regulator cytotoxic T-lymphocyte antigen 4. Pharmacologic inhibition of these processes significantly reduces the oncolytic activity of ΔPK. PMID:26602205

  15. In silico modelling of a cancer stem cell-targeting agent and its effects on tumour control during radiotherapy

    PubMed Central

    Marcu, Loredana G.; Marcu, David

    2016-01-01

    Head and neck cancers (HNC), like most solid tumours, contain a subpopulation of cancer stem cells (CSC) that are commonly responsible for treatment failure. Conventional therapies are unsuccessful in controlling CSCs, thus novel, targeting therapies are needed. A promising agent is ATRA (All-trans-retinoic acid) that was shown to induce CSC differentiation, cell cycle redistribution and CSCs radiosensitisation. To add to the limited data, this work simulated the effects of ATRA on a virtual HNC and evaluated tumour response to radiotherapy. A Monte Carlo technique was employed to grow a HNC consisting of all lineages of cancer cells. The biologically realistic input parameters led to a pre-treatment CSC population of 5.9%. The Linear Quadratic model was employed to simulate radiotherapy. ATRA-induced differentiation, cell arrest and apoptosis were modelled, based on literature data. While the effect of differentiation was marginal, the strongest influence on CSC subpopulation was displayed by ATRA’s cell arrest effect via an exponential behaviour of the dose-response curve. The apoptotic effect induced by ATRA shows linear correlation between the percentage of apoptotic cells and dose required to eradicate CSCs. In conclusion, ATRA is a potent CSC-targeting agent with viable impact on tumour control when combined with radiotherapy. PMID:27573059

  16. In silico modelling of a cancer stem cell-targeting agent and its effects on tumour control during radiotherapy.

    PubMed

    Marcu, Loredana G; Marcu, David

    2016-01-01

    Head and neck cancers (HNC), like most solid tumours, contain a subpopulation of cancer stem cells (CSC) that are commonly responsible for treatment failure. Conventional therapies are unsuccessful in controlling CSCs, thus novel, targeting therapies are needed. A promising agent is ATRA (All-trans-retinoic acid) that was shown to induce CSC differentiation, cell cycle redistribution and CSCs radiosensitisation. To add to the limited data, this work simulated the effects of ATRA on a virtual HNC and evaluated tumour response to radiotherapy. A Monte Carlo technique was employed to grow a HNC consisting of all lineages of cancer cells. The biologically realistic input parameters led to a pre-treatment CSC population of 5.9%. The Linear Quadratic model was employed to simulate radiotherapy. ATRA-induced differentiation, cell arrest and apoptosis were modelled, based on literature data. While the effect of differentiation was marginal, the strongest influence on CSC subpopulation was displayed by ATRA's cell arrest effect via an exponential behaviour of the dose-response curve. The apoptotic effect induced by ATRA shows linear correlation between the percentage of apoptotic cells and dose required to eradicate CSCs. In conclusion, ATRA is a potent CSC-targeting agent with viable impact on tumour control when combined with radiotherapy. PMID:27573059

  17. Estrogen Regulates the Tumour Suppressor MiRNA-30c and Its Target Gene, MTA-1, in Endometrial Cancer

    PubMed Central

    Yan, Yuhua; Guo, Feifei; Li, Jian; Hu, Yali; Zhou, Huaijun; Xun, Qingying

    2014-01-01

    MicroRNA-30c (miR-30c) has been reported to be a tumour suppressor in endometrial cancer (EC). We demonstrate that miR-30c is down-regulated in EC tissue and is highly expressed in estrogen receptor (ER)-negative HEC-1-B cells. MiR-30c directly inhibits MTA-1 expression and functions as a tumour suppressor via the miR-30c-MTA-1 signalling pathway. Furthermore, miR-30c is decreased upon E2 treatment in both ER-positive Ishikawa and ER-negative HEC-1-B cells. Taken together, our results suggest that miR-30c is an important deregulated miRNA in EC and might serve as a potential biomarker and novel therapeutic target for EC. PMID:24595016

  18. Method for concentrating and purifying recombinant autonomous parvovirus vectors designed for tumour-cell-targeted gene therapy.

    PubMed

    Avalosse, B; Dupont, F; Spegelaere, P; Mine, N; Burny, A

    1996-12-01

    Recent work has highlighted the use of parvoviruses as potential vectors for tumour-cell-targeted gene therapy. The oncotropic properties of the prototype strain of minute virus of mice (MVMp) suggest that this virus might be a useful vehicle for introducing selectively therapeutic genes, e.g. lymphokine or suicide genes, into tumour cells and preferentially expressing them. But the low titre of recombinant virus stocks (10(5)-10(6) infectious units per ml) and their high level of contamination by cell proteins make it practically impossible to evaluate their efficacy in in vivo systems. A technique is described for producing cellular contaminant-free stocks of recombinant virus particles, with titres up to 5 x 10(8) IU/ml. PMID:9002076

  19. Metallothionein 1 h tumour suppressor activity in prostate cancer is mediated by euchromatin methyltransferase 1

    PubMed Central

    Han, Yu-Chen; Zheng, Zhong-Liang; Zuo, Ze-Hua; Yu, Yan P; Chen, Rui; Tseng, George C; Nelson, Joel B; Luo, Jian-Hua

    2014-01-01

    Metallothioneins (MTs) are a group of metal binding proteins thought to play a role in the detoxification of heavy metals. Here we showed by microarray and validation analyses that MT1h, a member of MT, is down-regulated in many human malignancies. Low expression of MT1h was associated with poor clinical outcomes in both prostate and liver cancer. We found that the promoter region of MT1h was hypermethylated in cancer and that demethylation of the MT1h promoter reversed the suppression of MT1h expression. Forced expression of MT1h induced cell growth arrest, suppressed colony formation, retarded migration, and reduced invasion. SCID mice with tumour xenografts with inducible MT1h expression had lower tumour volumes as well as fewer metastases and deaths than uninduced controls. MT1h was found to interact with euchromatin histone methyltransferase 1 (EHMT1) and enhanced its methyltransferase activity on histone 3. Knocking down of EHMT1 or a mutation in MT1h that abrogates its interaction with EHMT1 abrogated MT1h tumour suppressor activity. This demonstrates tumour suppressor activity in a heavy metal binding protein that is dependent on activation of histone methylation. PMID:23355073

  20. A robust screening method for dietary agents that activate tumour-suppressor microRNAs

    PubMed Central

    Hagiwara, Keitaro; Gailhouste, Luc; Yasukawa, Ken; Kosaka, Nobuyoshi; Ochiya, Takahiro

    2015-01-01

    Certain dietary agents, such as natural products, have been reported to show anti-cancer effects. However, the underlying mechanisms of these substances in human cancer remain unclear. We recently found that resveratrol exerts an anti-cancer effect by upregulating tumour-suppressor microRNAs (miRNAs). In the current study, we aimed to identify new dietary products that have the ability to activate tumour-suppressor miRNAs and that therefore may serve as novel tools for the prevention and treatment of human cancers. We describe the generation and use of an original screening system based on a luciferase-based reporter vector for monitoring miR-200c tumour-suppressor activity. By screening a library containing 139 natural substances, three natural compounds — enoxolone, magnolol and palmatine chloride — were identified as being capable of inducing miR-200c expression in breast cancer cells at 10 μM. Moreover, these molecules suppressed the invasiveness of breast cancer cells in vitro. Next, we identified a molecular pathway by which the increased expression of miR-200c induced by natural substances led to ZEB1 inhibition and E-cadherin induction. These results indicate that our method is a valuable tool for a fast identification of natural molecules that exhibit tumour-suppressor activity in human cancer through miRNA activation. PMID:26423775

  1. Dual targeting of Angiopoetin-2 and VEGF potentiates effective vascular normalisation without inducing empty basement membrane sleeves in xenograft tumours

    PubMed Central

    Coutelle, O; Schiffmann, L M; Liwschitz, M; Brunold, M; Goede, V; Hallek, M; Kashkar, H; Hacker, U T

    2015-01-01

    Background: Effective vascular normalisation following vascular endothelial growth factor (VEGF) inhibition is associated with endothelial cell regression leaving empty basement membrane sleeves (BMS). These long-lived BMS permit the rapid regrowth of tumour vasculature upon treatment cessation and promote resistance to VEGF-targeting drugs. Previous attempts at removing BMS have failed. Angiopoietin-2 (Ang2) is a vascular destabilizing factor that antagonises normalisation. We hypothesised that Ang2 inhibition could permit vascular normalisation at significantly reduced doses of VEGF inhibition, avoiding excessive vessel regression and the formation of empty BMS. Methods: Mice xenografted with human colorectal cancer cells (LS174T) were treated with low (0.5 mg kg−1) or high (5 mg kg−1) doses of the VEGF-targeting antibody bevacizumab with or without an Ang2 blocking peptibody L1-10. Tumour growth, BMS formation and normalisation parameters were examined including vessel density, pericyte coverage, adherence junctions, leakiness, perfusion, hypoxia and proliferation. Results: Dual targeting of VEGF and Ang2 achieved effective normalisation at only one-tenth of the dose required with bevacizumab alone. Pericyte coverage, vascular integrity, adherence junctions and perfusion as prerequisites for improved access of chemotherapy were improved without inducing empty BMS that facilitate rapid vascular regrowth. Conclusions: Dual targeting of VEGF and Ang2 can potentiate the effectiveness of VEGF inhibitors and avoid the formation of empty BMS. PMID:25562438

  2. High Resolution In Vivo Bioluminescent Imaging for the Study of Bacterial Tumour Targeting

    PubMed Central

    Cronin, Michelle; Akin, Ali R.; Collins, Sara A.; Meganck, Jeff; Kim, Jae-Beom; Baban, Chwanrow K.; Joyce, Susan A.; van Dam, Gooitzen M.; Zhang, Ning; van Sinderen, Douwe; O'Sullivan, Gerald C.; Kasahara, Noriyuki; Gahan, Cormac G.; Francis, Kevin P.; Tangney, Mark

    2012-01-01

    The ability to track microbes in real time in vivo is of enormous value for preclinical investigations in infectious disease or gene therapy research. Bacteria present an attractive class of vector for cancer therapy, possessing a natural ability to grow preferentially within tumours following systemic administration. Bioluminescent Imaging (BLI) represents a powerful tool for use with bacteria engineered to express reporter genes such as lux. BLI is traditionally used as a 2D modality resulting in images that are limited in their ability to anatomically locate cell populations. Use of 3D diffuse optical tomography can localize the signals but still need to be combined with an anatomical imaging modality like micro-Computed Tomography (μCT) for interpretation. In this study, the non-pathogenic commensal bacteria E.coli K-12 MG1655 and Bifidobacterium breve UCC2003, or Salmonella Typhimurium SL7207 each expressing the luxABCDE operon were intravenously (IV) administered to mice bearing subcutaneous (s.c) FLuc-expressing xenograft tumours. Bacterial lux signal was detected specifically in tumours of mice post IV-administration and bioluminescence correlated with the numbers of bacteria recovered from tissue. Through whole body imaging for both lux and FLuc, bacteria and tumour cells were co-localised. 3D BLI and μCT image analysis revealed a pattern of multiple clusters of bacteria within tumours. Investigation of spatial resolution of 3D optical imaging was supported by ex vivo histological analyses. In vivo imaging of orally-administered commensal bacteria in the gastrointestinal tract (GIT) was also achieved using 3D BLI. This study demonstrates for the first time the potential to simultaneously image multiple BLI reporter genes three dimensionally in vivo using approaches that provide unique information on spatial locations. PMID:22295120

  3. In vivo detection of small tumour lesions by multi-pinhole SPECT applying a 99mTc-labelled nanobody targeting the Epidermal Growth Factor Receptor

    PubMed Central

    Krüwel, Thomas; Nevoltris, Damien; Bode, Julia; Dullin, Christian; Baty, Daniel; Chames, Patrick; Alves, Frauke

    2016-01-01

    The detection of tumours in an early phase of tumour development in combination with the knowledge of expression of tumour markers such as epidermal growth factor receptor (EGFR) is an important prerequisite for clinical decisions. In this study we applied the anti-EGFR nanobody 99mTc-D10 for visualizing small tumour lesions with volumes below 100 mm3 by targeting EGFR in orthotopic human mammary MDA-MB-468 and MDA-MB-231 and subcutaneous human epidermoid A431 carcinoma mouse models. Use of nanobody 99mTc-D10 of a size as small as 15.5 kDa enables detection of tumours by single photon emission computed tomography (SPECT) imaging already 45 min post intravenous administration with high tumour uptake (>3% ID/g) in small MDA-MB-468 and A431 tumours, with tumour volumes of 52.5 mm3 ± 21.2 and 26.6 mm3 ± 16.7, respectively. Fast blood clearance with a serum half-life of 4.9 min resulted in high in vivo contrast and ex vivo tumour to blood and tissue ratios. In contrast, no accumulation of 99mTc-D10 in MDA-MB-231 tumours characterized by a very low expression of EGFR was observed. Here we present specific and high contrast in vivo visualization of small human tumours overexpressing EGFR by preclinical multi-pinhole SPECT shortly after administration of anti-EGFR nanobody 99mTc-D10. PMID:26912069

  4. In vivo detection of small tumour lesions by multi-pinhole SPECT applying a (99m)Tc-labelled nanobody targeting the Epidermal Growth Factor Receptor.

    PubMed

    Krüwel, Thomas; Nevoltris, Damien; Bode, Julia; Dullin, Christian; Baty, Daniel; Chames, Patrick; Alves, Frauke

    2016-01-01

    The detection of tumours in an early phase of tumour development in combination with the knowledge of expression of tumour markers such as epidermal growth factor receptor (EGFR) is an important prerequisite for clinical decisions. In this study we applied the anti-EGFR nanobody (99m)Tc-D10 for visualizing small tumour lesions with volumes below 100 mm(3) by targeting EGFR in orthotopic human mammary MDA-MB-468 and MDA-MB-231 and subcutaneous human epidermoid A431 carcinoma mouse models. Use of nanobody (99m)Tc-D10 of a size as small as 15.5 kDa enables detection of tumours by single photon emission computed tomography (SPECT) imaging already 45 min post intravenous administration with high tumour uptake (>3% ID/g) in small MDA-MB-468 and A431 tumours, with tumour volumes of 52.5 mm(3) ± 21.2 and 26.6 mm(3) ± 16.7, respectively. Fast blood clearance with a serum half-life of 4.9 min resulted in high in vivo contrast and ex vivo tumour to blood and tissue ratios. In contrast, no accumulation of (99m)Tc-D10 in MDA-MB-231 tumours characterized by a very low expression of EGFR was observed. Here we present specific and high contrast in vivo visualization of small human tumours overexpressing EGFR by preclinical multi-pinhole SPECT shortly after administration of anti-EGFR nanobody (99m)Tc-D10. PMID:26912069

  5. Biodistribution and pharmacokinetics of111In-DTPA-labelled pegylated liposomes in a human tumour xenograft model: implications for novel targeting strategies

    PubMed Central

    Harrington, K J; Rowlinson-Busza, G; Syrigos, K N; Uster, P S; Abra, R M; Stewart, J S W

    2000-01-01

    The biodistribution and pharmacokinetics of111In-DTPA-labelled pegylated liposomes in tumour-bearing nude mice was studied to examine possible applications of pegylated liposome-targeted anti-cancer therapies. Nude mice received an intravenous injection of 100 μl of111In-DTPA-labelled pegylated liposomes, containing 0.37–0.74 MBq of activity. The t 1/2α and t 1/2β of111In-DTPA-labelled pegylated liposomes were 1.1 and 10.3 h, respectively. Tumour uptake was maximal at 24 h at 5.5 ± 3.0% ID g–1. Significant reticuloendothelial system uptake was demonstrated with 19.3 ± 2.8 and 18.8 ± 4.2% ID g–1at 24 h in the liver and spleen, respectively. Other sites of appreciable deposition were the kidney, skin, female reproductive tract and to a lesser extent the gastrointestinal tract. There was no indication of cumulative deposition of pegylated liposomes in the lung, central nervous system, musculoskeletal system, heart or adrenal glands. In contrast, the t 1/2α and t 1/2β of unencapsulated111In-DTPA were 5 min and 1.1 h, respectively, with no evidence of accumulation in tumour or normal tissues. Incubation of111In-DTPA-labelled pegylated liposomes in human serum for up to 10 days confirmed that they are very stable, with only minor leakage of their contents. The potential applications of pegylated liposomes in the arena of targeted therapy of solid cancers are discussed. © 2000 Cancer Research Campaign PMID:10901376

  6. Anti-tumour activity of photodynamic therapy in combination with mitomycin C in nude mice with human colon adenocarcinoma.

    PubMed Central

    Ma, L. W.; Moan, J.; Steen, H. B.; Iani, V.

    1995-01-01

    The interaction of photodynamic therapy (PDT) and a chemotherapeutic drug, mitomycin C (MMC), was investigated using WiDr human colon adenocarcinoma tumours implanted on Balb/c athymic nude mice. The WiDr tumours were treated with PDT alone, MMC alone or with both. It was found that the combined treatment produced a greater retardation in the growth of the WiDr tumour than monotherapy with MMC or PDT. The synergistic effect was especially prominent when PDT was used in combination with a low dose of MMC (1 mg kg-1), since treatment of 1 mg kg-1 MMC alone had no effect on the tumour. The anti-tumour activity of PDT was found to be increased with MMC of 5 mg kg-1. The response of normal skin on mice feet to PDT slightly greater when PDT was combined with 5 mg kg-1 MMC than when PDT was applied alone, while no detectable additional effect on skin photosensitivity was observed when PDT was combined with 1 mg kg-1 MMC. An enhanced uptake of Photofrin in tumours was found 12 h and 24 h after administration of MMC. The effect of MMC on the cell cycle distribution of cell dissociated directly from the tumours was studied. The results suggest that the increased susceptibility to photoinactivation of Photofrin-sensitised tumours may be due to MMC-induced accumulation of the tumour cells in S-phase. PMID:7734319

  7. MMP7 is a target of the tumour-associated antigen EpCAM

    PubMed Central

    Denzel, Sabine; Mack, Brigitte; Eggert, Carola; Massoner, Petra; Stöcklein, Nikolas; Kemming, Dirk; Harréus, Ulrich; Gires, Olivier

    2012-01-01

    Epithelial cell adhesion molecule (EpCAM) is a single-transmembrane protein, which is involved in numerous cellular processes including cell adhesion, proliferation, maintenance of stemness of embryonic cells and progenitors, migration and invasion. Activation of signal transduction by EpCAM is warranted by regulated intramembrane proteolysis and nuclear translocation of the intracellular domain EpICD. Here, we describe matrix metalloproteinase 7 (MMP7) as a target gene of EpCAM signalling viaEpICD nuclear translocation. EpCAM and MMP7 expression pattern and levels positively correlated in vitro and in vivo, and were strongly elevated in primary carcinomas of the head and neck area. Hence, MMP7 is a novel target of EpCAM signalling. PMID:22974215

  8. Cytotoxic activity of an octadecenoic acid extract from Euphorbia kansui (Euphorbiaceae) on human tumour cell strains.

    PubMed

    Yu, Farong; Lu, Shunqing; Yu, Fahong; Shi, Junnian; McGuire, Peter M; Wang, Rui

    2008-02-01

    We have investigated the cytotoxic and antitumour activity of an octadecenoic acid extract, mainly containing oleic and linoleic acids, from Euphorbia kansui on human gastric (SGC-7901), hepatocellular carcinoma (BEL-7402), and leukaemia (HL-60) tumour cell strains. Significant and dose-dependent antiproliferation effects were observed on tumour cells from the dose of 3.2 microg mL(-1), which were comparable with or better than those of the common antitumour agent 5-fluorouracil. Results from the clone formation assay and flow cytometry indicated that the mixture of octadecenoic acids resulted in a dose-dependent reduction in the number of tumour cells and significantly inhibited cell proliferation, with induced apoptosis and G(0)/G(1) phase cell cycle arrest. Also, the octadecenoic acids could not only cause cell apoptosis/necrosis but also functionally and structurally damage the tumour cell membrane and cell ultra-structures. These observations encourage further clinical evaluation of the inhibitory effects of octadecenoic acids on various forms of cancer. PMID:18237474

  9. miR‐490‐5p suppresses tumour growth in renal cell carcinoma through targeting PIK3CA

    PubMed Central

    Chen, Ke; Zeng, Jin; Tang, Kun; Xiao, Haibing; Hu, Junhui; Huang, Chunhua; Yao, Weimin; Yu, Gan; Xiao, Wei; Guan, Wei; Guo, Xiaolin; Xu, Hua

    2015-01-01

    Background Information Dysregulated micro‐RNAs have been reported in many human cancers, including renal cell carcinoma. Recent studies indicated that miR‐490 is involved in tumour development and progression. However, the expression profile and function in renal cell carcinoma remains unknown. Results Herein, we showed that miR‐490‐5p was down‐regulated in renal cell carcinoma tissues and cells compared with the adjacent normal tissues and normal cells. We also provided evidence that miR‐490‐5p acts as a tumour suppressor in renal carcinoma in a variety of in vitro and in vivo assays. Mechanistically, miR‐490‐5p was verified to directly bind to 3′ UTR of the PIK3CA mRNA and reduce the expression of PIK3CA at both mRNA and protein levels, which further inhibits phosphatidylinositol 3‐kinase/Akt signalling pathway. We further showed that knockdown of PIK3CA can block the growth inhibitory effect of miR‐490‐5p, and over‐expression of PIK3CA can reverse the inhibitory effect of miR‐490‐5p on renal cancer cell tumourigenicity. Conclusions Taken together, our results indicated for the first time that miR‐490‐5p functions as a tumour suppressor in renal carcinoma by targeting PIK3CA. Significance Our findings suggest that miR‐490‐5p may be a potential gene therapy target for the treatment of renal cell carcinoma. PMID:26559013

  10. ERas protein is overexpressed and binds to the activated platelet-derived growth factor β receptor in bovine urothelial tumour cells associated with papillomavirus infection.

    PubMed

    Russo, Valeria; Roperto, Franco; Esposito, Iolanda; Ceccarelli, Dora Maria; Zizzo, Nicola; Leonardi, Leonardo; Capparelli, Rosanna; Borzacchiello, Giuseppe; Roperto, Sante

    2016-06-01

    Embryonic stem cell-expressed Ras (ERas) encodes a constitutively active form of guanosine triphosphatase (GTPase) that binds to and activates phosphatidylinositol 3 kinase (PI3K), which in turn phosphorylates and activates downstream targets such as Akt. The current study evaluated ERas regulation and expression in papillomavirus-associated urothelial tumours in cattle grazing on lands rich in bracken fern. ERas was found upregulated and overexpressed by PCR, real time PCR and Western blot. Furthermore, protein overexpression was also confirmed by immunohistochemistry. ERas was found to interact physically and colocalise with the activated platelet derived growth factor β receptor (PDGFβR) by coimmunoprecipitation and laser scanning confocal investigations. Phosphorylation of Akt, a downstream effector both of ERas and PDGFβR, appeared to be increased in urothelial tumour cells. Altogether, these data indicate that ERas/PDGFβR complex could play a role in the pathogenesis of bovine papillomavirus-associated bladder neoplasia. PMID:27256024

  11. Targeting tumour vasculature by inhibiting activin receptor-like kinase (ALK)1 function.

    PubMed

    de Vinuesa, Amaya García; Bocci, Matteo; Pietras, Kristian; Ten Dijke, Peter

    2016-08-15

    Angiogenesis is a hallmark of cancer and is now a validated therapeutic target in the clinical setting. Despite the initial success, anti-angiogenic compounds impinging on the vascular endothelial growth factor (VEGF) pathway display limited survival benefits in patients and resistance often develops due to activation of alternative pathways. Thus, finding and validating new targets is highly warranted. Activin receptor-like kinase (ALK)1 is a transforming growth factor beta (TGF-β) type I receptor predominantly expressed in actively proliferating endothelial cells (ECs). ALK1 has been shown to play a pivotal role in regulating angiogenesis by binding to bone morphogenetic protein (BMP)9 and 10. Two main pharmacological inhibitors, an ALK1-Fc fusion protein (Dalantercept/ACE-041) and a fully human antibody against the extracellular domain of ALK1 (PF-03446962) are currently under clinical development. Herein, we briefly recapitulate the role of ALK1 in blood vessel formation and the current status of the preclinical and clinical studies on inhibition of ALK1 signalling as an anti-angiogenic strategy. Future directions in terms of new combination regimens will also be presented. PMID:27528762

  12. Prostate tumour overexpressed-1 promotes tumourigenicity in human breast cancer via activation of Wnt/β-catenin signalling.

    PubMed

    Cui, Yanmei; Ma, Weifeng; Lei, Fangyong; Li, Qingyuan; Su, Yanhong; Lin, Xi; Lin, Chuyong; Zhang, Xin; Ye, Liping; Wu, Shu; Li, Jun; Yuan, Zhongyu; Song, Libing

    2016-07-01

    Breast cancer is the most common malignancy in females. The presence of cancer stem cells (CSCs) is the main cause of local and distant tumour recurrence and is associated with poor outcome in breast cancer. However, the molecular mechanisms underlying the maintenance of CSCs remain largely unknown. This study demonstrates that prostate tumour overexpressed-1 (PTOV1) enhances the CSC population and augments the tumourigenicity of breast cancer cells both in vitro and in vivo. Moreover, PTOV1 suppresses transcription of Dickkopf-1 (DKK1) by recruiting histone deacetylases and subsequently reducing DKK1 promoter histone acetylation, followed by activation of Wnt/β-catenin signalling. Restoration of DKK1 expression in PTOV1-overexpressing cells counteracts the effects of PTOV1 on Wnt/β-catenin activation and the CSC population. Collectively, these results suggest that PTOV1 positively regulates the Wnt/β-catenin signalling pathway and enhances tumourigenicity in breast cancer; this novel mechanism may represent a therapeutic target for breast cancer. Copyright © 2016 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. PMID:27060981

  13. Molecular profiling of tumour budding implicates TGFβ-mediated epithelial-mesenchymal transition as a therapeutic target in oral squamous cell carcinoma.

    PubMed

    Jensen, D H; Dabelsteen, E; Specht, L; Fiehn, A M K; Therkildsen, M H; Jønson, L; Vikesaa, J; Nielsen, F C; von Buchwald, C

    2015-08-01

    Although tumour budding is an adverse prognostic factor for many cancer types, the molecular mechanisms governing this phenomenon are incompletely understood. Therefore, understanding the molecular basis of tumour budding may provide new therapeutic and diagnostic options. We employ digital image analysis to demonstrate that the number of tumour buds in cytokeratin-stained sections correlates with patients having lymph node metastases at diagnosis. The tumour bud count was also a predictor of overall survival, independent of TNM stage. Tumour buds and paired central tumour areas were subsequently collected from oral squamous cell carcinoma (OSCC) specimens, using laser capture microdissection, and examined with RNA sequencing and miRNA-qPCR arrays. Compared with cells from the central parts of the tumours, budding cells exhibited a particular gene expression signature, comprising factors involved in epithelial-mesenchymal transition (EMT) and activated TGFβ signalling. Transcription factors ZEB1 and PRRX1 were up-regulated concomitantly with the decreased expression of mesenchymal-epithelial (MET) transcription factors (eg OVOL1) in addition to Krüppel-like factors and Grainyhead-like factors. Moreover, miR-200 family members were down-regulated in budding tumour cells. We used immunohistochemistry to validate five markers of the EMT/MET process in 199 OSCC tumours, as well as in situ hybridization in 20 OSCC samples. Given the strong relationship between tumour budding and the development of lymph node metastases and an adverse prognosis, therapeutics based on inhibiting the activation of TGFβ signalling may prove useful in the treatment of OSCC. PMID:25925492

  14. Plant Virus Particles Carrying Tumour Antigen Activate TLR7 and Induce High Levels of Protective Antibody

    PubMed Central

    Jobsri, Jantipa; Allen, Alex; Rajagopal, Deepa; Shipton, Michael; Kanyuka, Kostya; Lomonossoff, George P.; Ottensmeier, Christian; Diebold, Sandra S.; Stevenson, Freda K.; Savelyeva, Natalia

    2015-01-01

    Induction of potent antibody is the goal of many vaccines targeted against infections or cancer. Modern vaccine designs that use virus-like particles (VLP) have shown efficacy for prophylactic vaccination against virus-associated cancer in the clinic. Here we used plant viral particles (PVP), which are structurally analogous to VLP, coupled to a weak idiotypic (Id) tumour antigen, as a conjugate vaccine to induce antibody against a murine B-cell malignancy. The Id-PVP vaccine incorporates a natural adjuvant, the viral ssRNA, which acts via TLR7. It induced potent protective anti-Id antibody responses in an in vivo mouse model, superior to the “gold standard” Id vaccine, with prevalence of the IgG2a isotype. Combination with alum further increased antibody levels and maintained the IgG2a bias. Engagement of TLR7 in vivo was followed by secretion of IFN-α by plasmacytoid dendritic cells and by activation of splenic CD11chi conventional dendritic cells. The latter was apparent from up-regulation of co-stimulatory molecules and from secretion of a wide range of inflammatory cytokines and chemokines including the Th1-governing cytokine IL-12, in keeping with the IgG2a antibody isotype distribution. PVP conjugates are a novel cancer vaccine design, offering an attractive molecular form, similar to VLP, and providing T-cell help. In contrast to VLP, they also incorporate a safe “in-built” ssRNA adjuvant. PMID:25692288

  15. Hypoxic repression of pyruvate dehydrogenase activity is necessary for metabolic reprogramming and growth of model tumours

    PubMed Central

    Golias, Tereza; Papandreou, Ioanna; Sun, Ramon; Kumar, Bhavna; Brown, Nicole V.; Swanson, Benjamin J.; Pai, Reetesh; Jaitin, Diego; Le, Quynh-Thu; Teknos, Theodoros N.; Denko, Nicholas C.

    2016-01-01

    Tumour cells fulfil the bioenergetic and biosynthetic needs of proliferation using the available environmental metabolites. Metabolic adaptation to hypoxia causes decreased mitochondrial function and increased lactate production. This work examines the biological importance of the hypoxia-inducible inhibitory phosphorylations on the pyruvate dehydrogenase E1α subunit. Pancreatic cancer cell lines were genetically manipulated to alter the net phosphorylation of PDH E1α through reduced kinase expression or enhanced phosphatase expression. The modified cells were tested for hypoxic changes in phosphorylated E1α, mitochondrial metabolism and growth as xenografted tumours. Even though there are four PDHK genes, PDHK1 is essential for inhibitory PDH phosphorylation of E1α at serine 232, is partially responsible for modification of serines 293 and 300, and these phosphorylations are necessary for model tumour growth. In order to determine the clinical relevance, a cohort of head and neck cancer patient biopsies was examined for phosphorylated E1α and expression of PDHK1. Patients with detectable 232 phosphorylation or expression of PDHK1 tend to have worse clinical outcome. These data show that PDHK1 activity is unique and non-redundant in the family of PHDK enzymes and a PDHK1 specific inhibitor would therefore have anti-cancer activity with reduced chance of side effects from inhibition of other PDHKs. PMID:27498883

  16. Hypoxic repression of pyruvate dehydrogenase activity is necessary for metabolic reprogramming and growth of model tumours.

    PubMed

    Golias, Tereza; Papandreou, Ioanna; Sun, Ramon; Kumar, Bhavna; Brown, Nicole V; Swanson, Benjamin J; Pai, Reetesh; Jaitin, Diego; Le, Quynh-Thu; Teknos, Theodoros N; Denko, Nicholas C

    2016-01-01

    Tumour cells fulfil the bioenergetic and biosynthetic needs of proliferation using the available environmental metabolites. Metabolic adaptation to hypoxia causes decreased mitochondrial function and increased lactate production. This work examines the biological importance of the hypoxia-inducible inhibitory phosphorylations on the pyruvate dehydrogenase E1α subunit. Pancreatic cancer cell lines were genetically manipulated to alter the net phosphorylation of PDH E1α through reduced kinase expression or enhanced phosphatase expression. The modified cells were tested for hypoxic changes in phosphorylated E1α, mitochondrial metabolism and growth as xenografted tumours. Even though there are four PDHK genes, PDHK1 is essential for inhibitory PDH phosphorylation of E1α at serine 232, is partially responsible for modification of serines 293 and 300, and these phosphorylations are necessary for model tumour growth. In order to determine the clinical relevance, a cohort of head and neck cancer patient biopsies was examined for phosphorylated E1α and expression of PDHK1. Patients with detectable 232 phosphorylation or expression of PDHK1 tend to have worse clinical outcome. These data show that PDHK1 activity is unique and non-redundant in the family of PHDK enzymes and a PDHK1 specific inhibitor would therefore have anti-cancer activity with reduced chance of side effects from inhibition of other PDHKs. PMID:27498883

  17. Immunohistochemical Detection of Urokinase Plasminogen Activator and Urokinase Plasminogen Activator Receptor in Canine Vascular Endothelial Tumours.

    PubMed

    Anwar, Sh; Yanai, T; Sakai, H

    2015-11-01

    Immunohistochemistry was used to assess the expression of urokinase plasminogen activator (uPA) and uPA receptor (uPAR) in 57 canine primary haemangiosarcomas (HSAs), 26 canine cutaneous haemangiomas (HAs) and in control sections of canine cutaneous granulation tissue. The correlation between uPA/uPAR expression and the Ki67 labelling index (LI) was estimated in the HSA and HA tissues. uPA was expressed by 73.2% and 75.0% of splenic HSAs and non-splenic HSAs, respectively. All HSA tissues tested expressed uPAR. Expression of both molecules was significantly higher in HSAs than in cutaneous HAs (3.8% for uPA and 30.7% for uPAR). The average Ki67 LI of the uPA(+)/uPAR(+) HSAs was significantly higher than that of uPA(-)/uPAR(+) HSAs and HA tissues (mean ± SDs 32.8 ± 15.3, 15.2 ± 7.2 and 2.1 ± 0.7, respectively; P <0.05). These results suggest that uPA and uPAR play a significant role in the malignant proliferation of canine HSA, regardless of the primary origin of the tumour. PMID:26286429

  18. Photodynamic activity of BAM-SiPc, an unsymmetrical bisamino silicon(IV) phthalocyanine, in tumour-bearing nude mice

    PubMed Central

    Leung, S C H; Lo, P-C; Ng, D K P; Liu, W-K; Fung, K-P; Fong, W-P

    2008-01-01

    Background and purpose Ever since the discovery of photodynamic therapy, there has been a continuous search for more potent photosensitizers. Towards that end, we have synthesized a number of novel phthalocyanine derivatives. The unsymmetrical bisamino silicon(IV) phthalocyanine BAM-SiPc is one of the most potent compounds. In in vitro cell culture, it exhibits high phototoxicity against a number of cancer cell lines. Experimental approach In the present investigation, the in vivo effect of BAM-SiPc was studied in the tumour-bearing nude mice model. The biodistribution of BAM-SiPc was followed to evaluate its tumour selectivity and rate of clearance. The tumour volume in the hepatocarcinoma HepG2- and the colorectal adenocarcinoma HT29-bearing nude mice was measured after photodynamic therapy. The level of intrinsic toxicity induced was also investigated. Finally, the metabolism of BAM-SiPc in the ‘normal' WRL68 liver cells and the hepatocarcinoma HepG2 cells was compared. Key results The results not only showed significant tumour regression of HepG2 and growth inhibition of HT29 in the tumour-bearing nude mice, but also no apparent hepatic or cardiac injury with the protocol used. Histological analyses showed that apoptosis was induced in the solid tumour. BAM-SiPc could be metabolized by WRL68 liver cells but not by the hepatocarcinoma HepG2 cells. Unfortunately, BAM-SiPc did not show any specific targeting towards the tumour tissue. Conclusions and implications The efficiency of BAM-SiPc in inhibiting tumour growth makes it a good candidate for further evaluation. Enhancement of its uptake in tumour tissue by conjugation with biomolecules is currently under investigation. PMID:18332853

  19. Sensitive β-galactosidase-targeting fluorescence probe for visualizing small peritoneal metastatic tumours in vivo.

    PubMed

    Asanuma, Daisuke; Sakabe, Masayo; Kamiya, Mako; Yamamoto, Kyoko; Hiratake, Jun; Ogawa, Mikako; Kosaka, Nobuyuki; Choyke, Peter L; Nagano, Tetsuo; Kobayashi, Hisataka; Urano, Yasuteru

    2015-01-01

    Fluorescence-guided diagnostics is one of the most promising approaches for facile detection of cancer in situ. Here we focus on β-galactosidase, which is overexpressed in primary ovarian cancers, as a molecular target for visualizing peritoneal metastases from ovarian cancers. As existing fluorescence probes are unsuitable, we have designed membrane-permeable HMRef-βGal, in which the optimized intramolecular spirocyclic function affords >1,400-fold fluorescence enhancement on activation. We confirm that HMRef-βGal sensitively detects intracellular β-galactosidase activity in several ovarian cancer lines. In vivo, this probe visualizes metastases as small as <1 mm in diameter in seven mouse models of disseminated human peritoneal ovarian cancer (SHIN3, SKOV3, OVK18, OVCAR3, OVCAR4, OVCAR5 and OVCAR8). Because of its high brightness, real-time detection of metastases with the naked eye is possible. Endoscopic fluorescence detection of metastases is also demonstrated. The results clearly indicate preclinical potential value of the probe for fluorescence-guided diagnosis of peritoneal metastases from ovarian cancers. PMID:25765713

  20. Sensitive β-galactosidase-targeting fluorescence probe for visualizing small peritoneal metastatic tumours in vivo

    PubMed Central

    Asanuma, Daisuke; Sakabe, Masayo; Kamiya, Mako; Yamamoto, Kyoko; Hiratake, Jun; Ogawa, Mikako; Kosaka, Nobuyuki; Choyke, Peter L.; Nagano, Tetsuo; Kobayashi, Hisataka; Urano, Yasuteru

    2015-01-01

    Fluorescence-guided diagnostics is one of the most promising approaches for facile detection of cancer in situ. Here we focus on β-galactosidase, which is overexpressed in primary ovarian cancers, as a molecular target for visualizing peritoneal metastases from ovarian cancers. As existing fluorescence probes are unsuitable, we have designed membrane-permeable HMRef-βGal, in which the optimized intramolecular spirocyclic function affords >1,400-fold fluorescence enhancement on activation. We confirm that HMRef-βGal sensitively detects intracellular β-galactosidase activity in several ovarian cancer lines. In vivo, this probe visualizes metastases as small as <1 mm in diameter in seven mouse models of disseminated human peritoneal ovarian cancer (SHIN3, SKOV3, OVK18, OVCAR3, OVCAR4, OVCAR5 and OVCAR8). Because of its high brightness, real-time detection of metastases with the naked eye is possible. Endoscopic fluorescence detection of metastases is also demonstrated. The results clearly indicate preclinical potential value of the probe for fluorescence-guided diagnosis of peritoneal metastases from ovarian cancers. PMID:25765713

  1. A dimensionless dynamic contrast enhanced MRI parameter for intra-prostatic tumour target volume delineation: initial comparison with histology

    NASA Astrophysics Data System (ADS)

    Hrinivich, W. Thomas; Gibson, Eli; Gaed, Mena; Gomez, Jose A.; Moussa, Madeleine; McKenzie, Charles A.; Bauman, Glenn S.; Ward, Aaron D.; Fenster, Aaron; Wong, Eugene

    2014-03-01

    Purpose: T2 weighted and diffusion weighted magnetic resonance imaging (MRI) show promise in isolating prostate tumours. Dynamic contrast enhanced (DCE)-MRI has also been employed as a component in multi-parametric tumour detection schemes. Model-based parameters such as Ktrans are conventionally used to characterize DCE images and require arterial contrast agent (CR) concentration. A robust parameter map that does not depend on arterial input may be more useful for target volume delineation. We present a dimensionless parameter (Wio) that characterizes CR wash-in and washout rates without requiring arterial CR concentration. Wio is compared to Ktrans in terms of ability to discriminate cancer in the prostate, as demonstrated via comparison with histology. Methods: Three subjects underwent DCE-MRI using gadolinium contrast and 7 s imaging temporal resolution. A pathologist identified cancer on whole-mount histology specimens, and slides were deformably registered to MR images. The ability of Wio maps to discriminate cancer was determined through receiver operating characteristic curve (ROC) analysis. Results: There is a trend that Wio shows greater area under the ROC curve (AUC) than Ktrans with median AUC values of 0.74 and 0.69 respectively, but the difference was not statistically significant based on a Wilcoxon signed-rank test (p = 0.13). Conclusions: Preliminary results indicate that Wio shows potential as a tool for Ktrans QA, showing similar ability to discriminate cancer in the prostate as Ktrans without requiring arterial CR concentration.

  2. Enhancement of bioreductive drug toxicity in murine tumours by inhibition of the activity of nitric oxide synthase.

    PubMed Central

    Butler, S. A.; Wood, P. J.; Cole, S.; Williams, C.; Adams, G. E.; Stratford, I. J.

    1997-01-01

    Nitro-L-arginine inhibits the production of nitric oxide and can thereby cause vasoconstriction in vivo. One consequence of this is that nitro-L-arginine can increase hypoxia in a range of transplantable and spontaneous murine solid tumours. Bioreductive drugs such as RB6145 are more active under hypoxic conditions, and the combination of RB6145 with nitro-L-arginine in vivo shows greater anti-tumour activity than either agent individually. In mice given nitro-L-arginine at 10 mg kg(-1) i.p. up to 1 h before or after 300 mg kg(-1) i.p. RB6145, survival of KHT tumour cells was reduced by 3-4 logs when assessed by clonogenic assay 24 h after treatment. RB6145 or nitro-L-arginine alone caused no more than 20% cell kill. Similar effects were found in SCCVII tumours. The tumour response to the drug combination was tumour size dependent, with increased tumour cell sensitivity occurring when the tumour volume at the time of treatment was increased. Further, the response of KHT tumours to the combination of RB6145 and nitro-L-arginine was also dependent on the time interval between treatment and on when tumours were excised for determination of survival in vitro. The relative surviving fraction was about 0.3 for intervals less than 4 h but was reduced to 0.01 at 12 h and 0.001 at 24 h. These results were supported by histological examination of tumours, when necrosis at 2 h after treatment was less than 5% but increased to greater than 90% at 24 h. RB6145-induced normal tissue damage, as measured by CFU-A survival, was not altered by combining with nitro-L-arginine. Hence, this drug combination may provide therapeutic benefit. It is likely that the substantial anti-tumour effects are due to enhancement of bioreductive toxicity through increased tumour hypoxia, although additional mechanism(s) may also contribute to the overall response. Images Figure 4 PMID:9275019

  3. The effect of calcium ions on the glycolytic activity of Ehrlich ascites-tumour cells

    PubMed Central

    Bygrave, F. L.

    1966-01-01

    1. Added Ca2+ inhibited lactate formation from sugar phosphates by intact Ehrlich ascites-tumour cells. Lactate formation from glucose by these cells was unaffected by added Ca2+. 2. The Ca2+ inhibition of lactate formation by intact cells occurred in the extracellular medium. 3. Intact ascites-tumour cells did not take up Ca2+ in vitro. 4. Glycolysis of sugar phosphates by cell extracts as well as pyruvate formation from 3-phosphoglycerate and phosphoenolpyruvate was inhibited by Ca2+. 5. It was concluded that Ca2+ inhibited the pyruvate-kinase (EC 2.7.1.40) reaction. Further, Ca2+ inhibition of pyruvate kinase could be correlated with the overall inhibition of glycolysis. 6. Concentrations of Ca2+ usually present in Krebs–Ringer buffers, inhibited glycolysis and pyruvate-kinase activity by approx. 50%. 7. The inhibition of glycolysis by added Ca2+ could be partially reversed by K+ and completely reversed by Mg2+ or by stoicheiometric amounts of EDTA. 8. The hypothesis is advanced that the inability of tumour cells to take up Ca2+ is a factor contributing towards their high rate of glycolysis. PMID:6007855

  4. Equine Cutaneous Mast Cell Tumours Exhibit Variable Differentiation, Proliferation Activity and KIT Expression.

    PubMed

    Ressel, L; Ward, S; Kipar, A

    2015-11-01

    Equine cutaneous mast cell tumours (CMCTs) are generally considered to be benign skin lesions, although recurrent and multicentric tumours have been described. For canine CMCTs, grading and prognostic approaches are well established and aberrant KIT expression as well as high proliferation indices are associated with poor outcome. However, in the case of equine CMCTs, morphological features, proliferative activity and KIT expression pattern have not been assessed or related to biological behaviour, and there is discussion as to whether CMCTs are true neoplastic processes. The present study describes 45 equine CMCTs in terms of their morphology and KIT and PCNA expression by immunohistochemistry. KIT expression was classified as membranous (I), cytoplasmic and focally stippled (II) or diffuse cytoplasmic (III). A large proportion of the tumours were multinodular or diffuse dermal infiltrates of mast cells with mild anisokaryosis, a low proliferative rate and a dominance of KIT pattern I, representing well-differentiated CMCTs. In approximately one third of the cases, the mast cells exhibited more infiltrative growth, moderate to marked anisokaryosis and a higher degree of proliferation. These were classified as poorly differentiated CMCTs and exhibited only KIT patterns II and III. These findings indicate that there is a subgroup of poorly differentiated equine CMCTs, in which there is an association between aberrant KIT expression, high proliferative rate and potential aggressive behaviour, all features that confirm at least the poorly differentiated CMCT as a true neoplastic processes. PMID:26292768

  5. CD28 co-stimulation via tumour-specific chimaeric receptors induces an incomplete activation response in Epstein-Barr virus-specific effector memory T cells.

    PubMed

    Altvater, B; Pscherer, S; Landmeier, S; Niggemeier, V; Juergens, H; Vormoor, J; Rossig, C

    2006-06-01

    Expression of tumour antigen-specific chimaeric receptors in T lymphocytes can redirect their effector functions towards tumour cells. Integration of the signalling domains of the co-stimulatory molecule CD28 into chRec enhances antigen-specific proliferation of polyclonal human T cell populations. While CD28 plays an essential role in the priming of naive CD4(+) T cells, its contribution to effector memory T cell responses is controversial. We compared the function of the chRec with and without the CD28 co-stimulatory domain, expressing it in peripheral blood T cells or Epstein-Barr virus (EBV)-specific T cell lines. The chimaeric T cell receptors contain an extracellular single-chain antibody domain, to give specificity against the tumour ganglioside antigen G(D2). The transduced cytotoxic T lymphocytes (CTL) maintained their specificity for autologous EBV targets and their capacity to proliferate after stimulation with EBV-infected B cells. Intracellular cytokine staining demonstrated efficient and comparable antigen-specific interferon (IFN)-gamma secretion by CTL following engagement of both the native and the chimaeric receptor, independent of chimaeric CD28 signalling. Furthermore, tumour targets were lysed in an antigen-specific manner by both chRec. However, while antigen engagement by CD28 zeta chRec efficiently induced expansion of polyclonal peripheral blood lymphocytes in an antigen-dependent manner, CD28 signalling did not induce proliferation of EBV-CTL in response to antigen-expressing tumour cells. Thus, the co-stimulatory requirement for the efficient activation response of antigen-specific memory cells cannot be mimicked simply by combining CD28 and zeta signalling. The full potential of this highly cytolytic T cell population for adoptive immunotherapy of cancer requires further exploration of their co-stimulatory requirements. PMID:16734614

  6. IGF-1 drives chromogranin A secretion via activation of Arf1 in human neuroendocrine tumour cells

    PubMed Central

    Münzberg, Christin; Höhn, Katharina; Krndija, Denis; Maaß, Ulrike; Bartsch, Detlef K; Slater, Emily P; Oswald, Franz; Walther, Paul; Seufferlein, Thomas; von Wichert, Götz

    2015-01-01

    Hypersecretion is the major symptom of functional neuroendocrine tumours. The mechanisms that contribute to this excessive secretion of hormones are still elusive. A key event in secretion is the exit of secretory products from the Golgi apparatus. ADP-ribosylation factor (Arf) GTPases are known to control vesicle budding and trafficking, and have a leading function in the regulation of formation of secretory granula at the Golgi. Here, we show that Arf1 is the predominant Arf protein family member expressed in the neuroendocrine pancreatic tumour cell lines BON and QGP-1. In BON cells Arf1 colocalizes with Golgi markers as well as chromogranin A, and shows significant basal activity. The inhibition of Arf1 activity or expression significantly impaired secretion of chromogranin A. Furthermore, we show that the insulin-like growth factor 1 (IGF-1), a major regulator of growth and secretion in BON cells, induces Arf1 activity. We found that activation of Arf1 upon IGF-1 receptor stimulation is mediated by MEK/ERK signalling pathway in BON and QGP-1 cells. Moreover, the activity of Arf1 in BON cells is mediated by autocrinely secreted IGF-1, and concomitantly, autocrine IGF1 secretion is maintained by Arf1 activity. In summary, our data indicate an important regulatory role for Arf1 at the Golgi in hypersecretion in neuroendocrine cancer cells. PMID:25754106

  7. Tumour necrosis factor (TNF) as a mediator of macrophage helminthotoxic activity.

    PubMed

    James, S L; Glaven, J; Goldenberg, S; Meltzer, M S; Pearce, E

    1990-01-01

    Lymphokine-activated macrophages are cytotoxic for larvae of the helminth parasite Schistosoma mansoni. That soluble secreted factors may mediate this cytotoxicity was suggested by the observation that culture supernatant fluids from stimulated macrophages also exhibited larvacidal activity. These fluids contain the monokine tumour necrosis factor (TNF). Several observations indicated that TNF is directly toxic to schistosome larvae. Cytotoxic sera taken from BCG- or S. mansoni-immunized mice after endotoxin challenge killed schistosomula in vitro, and upon gel filtration the larvacidal factor(s) in the sera co-eluted with the tumoricidal activity defined as TNF. Recombinant-derived TNF exhibited direct toxicity to schistosomula at high concentrations, or at lower concentrations in the presence of IFN gamma. The larvacidal activity of macrophage supernatant fluids was abrogated by addition of either anti-TNF antisera or Zn+2, which has been shown to inhibit TNF-induced damage of tumour cells. Anti-TNF and Zn+2 likewise suppressed schistosomulum killing by lymphokine-activated peritoneal macrophages or the IC-21 macrophage line, indicating that TNF also plays a role in the effector mechanism of larval killing by whole cells. PMID:2314921

  8. Tumour suppressor death-associated protein kinase targets cytoplasmic HIF-1α for Th17 suppression

    PubMed Central

    Chou, Ting-Fang; Chuang, Ya-Ting; Hsieh, Wan-Chen; Chang, Pei-Yun; Liu, Hsin-Yu; Mo, Shu-Ting; Hsu, Tzu-Sheng; Miaw, Shi-Chuen; Chen, Ruey-Hwa; Kimchi, Adi; Lai, Ming-Zong

    2016-01-01

    Death-associated protein kinase (DAPK) is a tumour suppressor. Here we show that DAPK also inhibits T helper 17 (Th17) and prevents Th17-mediated pathology in a mouse model of autoimmunity. We demonstrate that DAPK specifically downregulates hypoxia-inducible factor 1α (HIF-1α). In contrast to the predominant nuclear localization of HIF-1α in many cell types, HIF-1α is located in both the cytoplasm and nucleus in T cells, allowing for a cytosolic DAPK–HIF-1α interaction. DAPK also binds prolyl hydroxylase domain protein 2 (PHD2) and increases HIF-1α-PHD2 association. DAPK thereby promotes the proline hydroxylation and proteasome degradation of HIF-1α. Consequently, DAPK deficiency leads to excess HIF-1α accumulation, enhanced IL-17 expression and exacerbated experimental autoimmune encephalomyelitis. Additional knockout of HIF-1α restores the normal differentiation of Dapk−/− Th17 cells and prevents experimental autoimmune encephalomyelitis development. Our results reveal a mechanism involving DAPK-mediated degradation of cytoplasmic HIF-1α, and suggest that raising DAPK levels could be used for treatment of Th17-associated inflammatory diseases. PMID:27312851

  9. Activation of the tumour suppressor kinase LKB1 by the STE20-like pseudokinase STRAD

    PubMed Central

    Baas, A.F.; Boudeau, J.; Sapkota, G.P.; Smit, L.; Medema, R.; Morrice, N.A.; Alessi, D.R.; Clevers, H.C.

    2003-01-01

    The LKB1 gene encodes a serine/threonine kinase mutated in Peutz–Jeghers cancer syndrome. Despite several proposed models for LKB1 function in development and in tumour suppression, the detailed molecular action of LKB1 remains undefined. Here, we report the identification and characterization of an LKB1-specific adaptor protein and substrate, STRAD (STe20 Related ADaptor). STRAD consists of a STE20- like kinase domain, but lacks several residues that are indispensable for intrinsic catalytic activity. Endo genous LKB1 and STRAD form a complex in which STRAD activates LKB1, resulting in phosphorylation of both partners. STRAD determines the subcellular localization of wild-type, but not mutant LKB1, translocating it from nucleus to cytoplasm. One LKB1 mutation previously identified in a Peutz–Jeghers family that does not compromise its kinase activity is shown here to interfere with LKB1 binding to STRAD, and hence with STRAD-dependent regulation. Removal of endogenous STRAD by siRNA abrogates the LKB1-induced G1 arrest. Our results imply that STRAD plays a key role in regulating the tumour suppressor activities of LKB1. PMID:12805220

  10. The locations of cathepsin activity and β-glucuronidase in the Guerin T8 tumour

    PubMed Central

    Poole, A. R.

    1970-01-01

    Tumour homogenate fractions, isolated by differential centrifugation, were subfractionated by density-gradient centrifugation. Biochemical and electron microscopic analyses revealed that β-glucuronidase and cathepsin activity were associated with a class (possibly two) of lysosomal particles of density greater than those of mitochondria and the endoplasmic reticulum. Lysosomes sedimented by low g forces were vacuolar, electron-dense, delineated by a unit membrane and about 0.2μm in diameter. β-Glucuronidase was also apparently associated with ribosomes whereas cathepsin was bound in part to the endoplasmic reticulum. Catalase and glucose 6-phosphatase possessed slightly different density-gradient sedimentation profiles. PMID:4319548

  11. Anti-tumour effects of antibodies targeting the extracellular cysteine-rich region of the receptor tyrosine kinase EphB4.

    PubMed

    Stephenson, Sally-Anne; Douglas, Evelyn L; Mertens-Walker, Inga; Lisle, Jessica E; Maharaj, Mohanan S N; Herington, Adrian C

    2015-04-10

    EphB4 is a membrane-bound receptor tyrosine kinase (RTK) commonly over-produced by many epithelial cancers but with low to no expression in most normal adult tissues. EphB4 over-production promotes ligand-independent signaling pathways that increase cancer cell viability and stimulate migration and invasion. Several studies have shown that normal ligand-dependent signaling is tumour suppressive and therefore novel therapeutics which block the tumour promoting ligand-independent signaling and/or stimulate tumour suppressive ligand-dependent signaling will find application in the treatment of cancer. An EphB4-specific polyclonal antibody, targeting a region of 200 amino acids in the extracellular portion of EphB4, showed potent in vitro anti-cancer effects measured by an increase in apoptosis and a decrease in anchorage independent growth. Peptide exclusion was used to identify the epitope targeted by this antibody within the cysteine-rich region of the EphB4 protein, a sequence defined as a potential ligand interacting interface. Addition of antibody to cancer cells resulted in phosphorylation and subsequent degradation of the EphB4 protein, suggesting a mechanism that is ligand mimetic and tumour suppressive. A monoclonal antibody which specifically targets this identified extracellular epitope of EphB4 significantly reduced breast cancer xenograft growth in vivo confirming that EphB4 is a useful target for ligand-mimicking antibody-based anti-cancer therapies. PMID:25831049

  12. Anti-tumour effects of antibodies targeting the extracellular cysteine-rich region of the receptor tyrosine kinase EphB4

    PubMed Central

    Stephenson, Sally-Anne; Douglas, Evelyn L.; Mertens-Walker, Inga; Lisle, Jessica E.; Maharaj, Mohanan S.N.; Herington, Adrian C.

    2015-01-01

    EphB4 is a membrane-bound receptor tyrosine kinase (RTK) commonly over-produced by many epithelial cancers but with low to no expression in most normal adult tissues. EphB4 over-production promotes ligand-independent signaling pathways that increase cancer cell viability and stimulate migration and invasion. Several studies have shown that normal ligand-dependent signaling is tumour suppressive and therefore novel therapeutics which block the tumour promoting ligand-independent signaling and/or stimulate tumour suppressive ligand-dependent signaling will find application in the treatment of cancer. An EphB4-specific polyclonal antibody, targeting a region of 200 amino acids in the extracellular portion of EphB4, showed potent in vitro anti-cancer effects measured by an increase in apoptosis and a decrease in anchorage independent growth. Peptide exclusion was used to identify the epitope targeted by this antibody within the cysteine-rich region of the EphB4 protein, a sequence defined as a potential ligand interacting interface. Addition of antibody to cancer cells resulted in phosphorylation and subsequent degradation of the EphB4 protein, suggesting a mechanism that is ligand mimetic and tumour suppressive. A monoclonal antibody which specifically targets this identified extracellular epitope of EphB4 significantly reduced breast cancer xenograft growth in vivo confirming that EphB4 is a useful target for ligand-mimicking antibody-based anti-cancer therapies. PMID:25831049

  13. Anti-tumour promoting activity of diphenylmethyl selenocyanate against two-stage mouse skin carcinogenesis.

    PubMed

    Das, Rajat Kumar; Bhattacharya, Sudin

    2005-01-01

    Epidemiological, clinical and experimental evidence collectively suggests that Se in different inorganic and organic forms provides a potential cancer chemopreventive agent, active against several types of cancer. It can exert preventive activity in all the three stages of cancer: initiation, promotion and progression. Literature reports revealed that organoselenocyanates have more potential as chemopreventive agents than inorganic forms due to their lower toxicity. In our previous report we showed chemopreventive efficacy of diphenylmethyl selenocyanate during the initiation and pre- plus post-initiation phases of skin and colon carcinogenesis process. The present study was undertaken to explore the anti-tumour promoting activity of diphenylmethyl selenocyanate in a 7,12-dimethylbenz (a) anthracene (DMBA)-croton oil two-stage skin carcinogenesis model. The results obtained showed significant (p<0.01) reduction of the incidence and number of skin papillomas, precancerous skin lesions, along with significant (p<0.01) elevation of phase II detoxifying enzymes (GST, Catalase and SOD) and inhibition of lipid peroxidation in liver and skin. Thus, the present data strongly suggest that diphenylmethyl selenocyanate also has the potential to act as anti-tumour promoter agent in a two-stage skin carcinogenesis mouse model, pointing to possible general efficacy. PMID:16101330

  14. Immunology in the clinic review series; focus on cancer: glycolipids as targets for tumour immunotherapy

    PubMed Central

    Durrant, L G; Noble, P; Spendlove, I

    2012-01-01

    Research into aberrant glycosylation and over-expression of glycolipids on the surface of the majority of cancers, coupled with a knowledge of glycolipids as functional molecules involved in a number of cellular physiological pathways, has provided a novel area of targets for cancer immunotherapy. This has resulted in the development of a number of vaccines and monoclonal antibodies that are showing promising results in recent clinical trials. PMID:22235996

  15. Isophosphoramide mustard, a metabolite of ifosfamide with activity against murine tumours comparable to cyclophosphamide.

    PubMed Central

    Struck, R. F.; Dykes, D. J.; Corbett, T. H.; Suling, W. J.; Trader, M. W.

    1983-01-01

    Isophosphoramide mustard was synthesized and was found to demonstrate activity essentially comparable to cyclophosphamide and ifosfamide against L1210 and P388 leukaemia. Lewis lung carcinoma, mammary adenocarcinoma 16/C, ovarian sarcoma M5076, and colon tumour 6A, in mice and Yoshida ascitic sarcoma in rats. At doses less than, or equivalent to, the LD10, isophosphoramide mustard retained high activity against cyclophosphamide-resistant L1210 and P388 leukaemias, but was less active against intracerebrally-implanted P388 leukaemia while cyclophosphamide produced a 4 log10 tumour cell reduction. It was also less active (one log10 lower cell kill) than cyclophosphamide against the B16 melonoma. Metabolism studies on ifosfamide in mice identified isophosphoramide mustard in blood. In addition, unchanged drug, carboxyifosfamide, 4-ketoifosfamide, dechloroethyl cyclophosphamide, dechloroethylifosfamide, and alcoifosfamide were identified. The latter 4 metabolites were also identified in urine from an ifosfamide-treated dog. In a simulated in vitro pharmacokinetic experiment against L1210 leukaemia in which drugs were incubated at various concentrations for various times, both 4-hydroxycyclophosphamide and isophosphoramide mustard exhibited significant cytoxicity at concentration times time values of 100-1000 micrograms X min ml-1, while acrolein was significantly cytotoxic at 10 micrograms X min ml-1. Treatment of mice with drug followed by L1210 cells demonstrated a shorter duration of effective levels of cytotoxic activity for isophosphoramide mustard and phosphoramide mustard in comparison with cyclophosphamide and ifosfamide. Isophosphoramide mustard and 2-chloroethylamine, a potential hydrolysis product of isophosphoramide mustard and carboxyifosfamide, were less mutagenic in the standard Ames test than the 2 corresponding metabolites of cyclophosphamide [phosphoramide mustard and bis(2-chloroethyl)amine]. PMID:6821629

  16. In vitro activity of bortezomib in cultures of patient tumour cells--potential utility in haematological malignancies.

    PubMed

    Wiberg, Kristina; Carlson, Kristina; Aleskog, Anna; Larsson, Rolf; Nygren, Peter; Lindhagen, Elin

    2009-01-01

    Bortezomib represents a new class of anti-cancer drugs, the proteasome inhibitors. We evaluated the in vitro activity of bortezomib with regard to tumour-type specificity and possible mechanisms of drug resistance in 115 samples of tumour cells from patients and in a cell-line panel, using the short-term fluorometric microculture cytotoxicity assay. Bortezomib generally showed dose-response curves with a steep slope. In patient cells, bortezomib was more active in haematological than in solid tumour samples. Myeloma and chronic myeloid leukaemia were the most sensitive tumour types although with great variability in drug response between the individual samples. Colorectal and kidney cancer samples were the least sensitive. In the cell-line panel, only small differences in response were seen between the different cell lines, and the proteasome inhibitors, lactacystin and MG 262, showed an activity pattern similar to that of bortezomib. The cell-line data suggest that resistance to bortezomib was not mediated by MRP-, PgP, GSH-; tubulin and topo II-associated MDR. Combination experiments indicated synergy between bortezomib and arsenic trioxide or irinotecan. The data support the current use of bortezomib but also points to its potential utility in other tumour types and in combination with cytotoxic drugs. PMID:19016012

  17. Combination cancer immunotherapies tailored to the tumour microenvironment.

    PubMed

    Smyth, Mark J; Ngiow, Shin Foong; Ribas, Antoni; Teng, Michele W L

    2016-03-01

    Evidence suggests that cancer immunotherapy will be a major part of the combination treatment plan for many patients with many cancer types in the near future. There are many types of immune processes involving different antitumour and tumour-promoting leucocytes, and tumour cells use many strategies to evade the immune response. The tumour microenvironment can help determine which immune suppressive pathways become activated to restrain antitumour immunity. This includes immune checkpoint receptors on effector T-cells and myeloid cells, and release of inhibitory cytokines and metabolites. Therapeutic approaches that target these pathways, particularly immune-checkpoint receptors, can induce durable antitumour responses in patients with advanced-stage cancers, including melanoma. Nevertheless, many patients do not have a good response to monotherapy approaches and alternative strategies are required to achieve optimal therapeutic benefit. These strategies include eliminating the bulk of tumour cells to provoke tumour-antigen release and antigen-presenting cell (APC) function, using adjuvants to enhance APC function, and using agents that enhance effector-cell activity. In this Review, we discuss the stratification of the tumour microenvironment according to tumour-infiltrating lymphocytes and PD-L1 expression in the tumour, and how this stratification enables the design of optimal combination cancer therapies tailored to target different tumour microenvironments. PMID:26598942

  18. In vitro performance of an injectable hydrogel/microsphere based immunocyte delivery system for localised anti-tumour activity.

    PubMed

    Wang, Chunming; Adrianus, Gerard N; Sheng, Nan; Toh, Shikai; Gong, Yihong; Wang, Dong-An

    2009-12-01

    The current practice of cell immunotherapy against cancer has encountered a substantial challenge, that is, targeted delivery of therapeutic cells to tumour sites is not favourably managed. In this study, we aimed to provide an engineering solution to govern the cell targeting and actions, for which a biomaterial model is developed to mediate the conveyance and accommodation of activated immunocytes with anti-cancer potentials. We fabricated a dual-layered hydrogel/microsphere (GS) composite, which preserves all advantageous features of hydrogel such as injectability and favourable permeability, to achieve genuine localisation and physical immobilisation of the executing immunocytes-macrophages. According to our presented in vitro investigations, the GS immunoconstruct exhibited effective elimination of carcinoma cells as well as high safety free of gene alteration or cell leakage. Notably, unwanted long-term proliferation of the delivered cells was restrained by physical encapsulation in the bio-inert 3D hydrogel frameworks. By these efforts, we have provided an immunocyte delivery platform with which cell-based immunotherapy can be initiated at a desired location and implemented in a controlled manner. PMID:19783044

  19. Kinase fusions are frequent in Spitz tumours and spitzoid melanomas

    NASA Astrophysics Data System (ADS)

    Wiesner, Thomas; He, Jie; Yelensky, Roman; Esteve-Puig, Rosaura; Botton, Thomas; Yeh, Iwei; Lipson, Doron; Otto, Geoff; Brennan, Kristina; Murali, Rajmohan; Garrido, Maria; Miller, Vincent A.; Ross, Jeffrey S.; Berger, Michael F.; Sparatta, Alyssa; Palmedo, Gabriele; Cerroni, Lorenzo; Busam, Klaus J.; Kutzner, Heinz; Cronin, Maureen T.; Stephens, Philip J.; Bastian, Boris C.

    2014-01-01

    Spitzoid neoplasms are a group of melanocytic tumours with distinctive histopathological features. They include benign tumours (Spitz naevi), malignant tumours (spitzoid melanomas) and tumours with borderline histopathological features and uncertain clinical outcome (atypical Spitz tumours). Their genetic underpinnings are poorly understood, and alterations in common melanoma-associated oncogenes are typically absent. Here we show that spitzoid neoplasms harbour kinase fusions of ROS1 (17%), NTRK1 (16%), ALK (10%), BRAF (5%) and RET (3%) in a mutually exclusive pattern. The chimeric proteins are constitutively active, stimulate oncogenic signalling pathways, are tumourigenic and are found in the entire biologic spectrum of spitzoid neoplasms, including 55% of Spitz naevi, 56% of atypical Spitz tumours and 39% of spitzoid melanomas. Kinase inhibitors suppress the oncogenic signalling of the fusion proteins in vitro. In summary, kinase fusions account for the majority of oncogenic aberrations in spitzoid neoplasms and may serve as therapeutic targets for metastatic spitzoid melanomas.

  20. C1q acts in the tumour microenvironment as a cancer-promoting factor independently of complement activation

    PubMed Central

    Bulla, Roberta; Tripodo, Claudio; Rami, Damiano; Ling, Guang Sheng; Agostinis, Chiara; Guarnotta, Carla; Zorzet, Sonia; Durigutto, Paolo; Botto, Marina; Tedesco, Francesco

    2016-01-01

    Complement C1q is the activator of the classical pathway. However, it is now recognized that C1q can exert functions unrelated to complement activation. Here we show that C1q, but not C4, is expressed in the stroma and vascular endothelium of several human malignant tumours. Compared with wild-type (WT) or C3- or C5-deficient mice, C1q-deficient (C1qa−/−) mice bearing a syngeneic B16 melanoma exhibit a slower tumour growth and prolonged survival. This effect is not attributable to differences in the tumour-infiltrating immune cells. Tumours developing in WT mice display early deposition of C1q, higher vascular density and an increase in the number of lung metastases compared with C1qa−/− mice. Bone marrow (BM) chimeras between C1qa−/− and WT mice identify non-BM-derived cells as the main local source of C1q that can promote cancer cell adhesion, migration and proliferation. Together these findings support a role for locally synthesized C1q in promoting tumour growth. PMID:26831747

  1. Multiple myeloma causes clonal T-cell immunosenescence: identification of potential novel targets for promoting tumour immunity and implications for checkpoint blockade.

    PubMed

    Suen, H; Brown, R; Yang, S; Weatherburn, C; Ho, P J; Woodland, N; Nassif, N; Barbaro, P; Bryant, C; Hart, D; Gibson, J; Joshua, D

    2016-08-01

    Tumour-induced dysfunction of cytotoxic T cells in patients with multiple myeloma (MM) may contribute to immune escape and be responsible for the lack of therapeutic efficacy of immune checkpoint blockade. We therefore investigated dysfunctional clonal T cells in MM and demonstrated immunosenescence but not exhaustion as a predominant feature. T-cell clones were detected in 75% of MM patients and their prognostic significance was revalidated in a new post-immunomodulatory drug cohort. The cells exhibited a senescent secretory effector phenotype: KLRG-1+/CD57+/CD160+/CD28-. Normal-for-age telomere lengths indicate that senescence is telomere independent and potentially reversible. p38-mitogen-activated protein kinase, p16 and p21 signalling pathways known to induce senescence were not elevated. Telomerase activity was found to be elevated and this may explain how normal telomere lengths are maintained in senescent cells. T-cell receptor signalling checkpoints were normal but elevated SMAD levels associated with T-cell inactivation were detected and may provide a potential target for the reversal of clonal T-cell dysfunction in MM. Low programmed death 1 and cytotoxic T-lymphocyte-associated antigen 4 expression detected on T-cell clones infers that these cells are not exhausted but suggests that there would be a suboptimal response to immune checkpoint blockade in MM. Our data suggest that other immunostimulatory strategies are required in MM. PMID:27102208

  2. MicroRNA-409 suppresses tumour cell invasion and metastasis by directly targeting radixin in gastric cancers.

    PubMed

    Zheng, B; Liang, L; Huang, S; Zha, R; Liu, L; Jia, D; Tian, Q; Wang, Q; Wang, C; Long, Z; Zhou, Y; Cao, X; Du, C; Shi, Y; He, X

    2012-10-18

    Emerging evidence has shown that aberrantly expressed microRNAs (miRNAs) are highly associated with tumour development and progression. However, little is known about the potential role of miRNAs in gastric cancer (GC) metastasis. In this study, miR-409-3p was found to be downregulated frequently in human GCs, and its expression was significantly associated with tumor-node-metastasis (TNM) stage and lymph node metastasis. Enforced expression of miR-409 in GC cells significantly reduced their migration and invasion in vitro and their capacity to develop distal pulmonary metastases and peritoneal dissemination in vivo. Moreover, we found that miR-409 exerted its function predominantly through the mature miR-409-3p, but not miR-409-5p. Microarray and bioinformatics analysis identified the pro-metastatic gene radixin (RDX) as a potential miR-409-3p target. Further studies confirmed that miR-409-3p suppressed the expression of RDX by directly binding to its 3'-untranslated region. Silencing of RDX by small interfering RNAs phenocopied the effects of miR-409 overexpression, whereas restoration of RDX in miR-409-overexpressed GC cells reversed the suppressive effects of miR-409. Taken together, these results demonstrate that miR-409 suppresses GC cell invasion and metastasis by directly targeting RDX and that patients with downregulated miR-409-3p are prone to lymph node metastasis. PMID:22179828

  3. Target for optically activated seekers and trackers

    NASA Astrophysics Data System (ADS)

    Lakin, C. T.; Willett, N. F.

    1984-05-01

    This abstract discloses a target for optically activated seekers and trackers (TOAST) which provides for calibrated and variable target characteristics such as size, intensity, spatial position, color and interfering background. The TOAST has a first ilumination system providing a target light beam through an adjustable iris which controls image size. The target beam passes through a collimator lens which focuses the light at infinity. With the target beam focused at infinity, the motion of an elevation plate lengthens or shortens the distance from the collimator lens to a one motion mirror. The target beam is attenuated by a variable filter driven by a servo-motor, and a color selection process is provided by passing the beam through spectral filters. A background light beam with background imagery is provided to the beamsplitter mirror and mixed with the target image so as to simulate the target environment encountered by an operating optically activated seeker and tracker.

  4. TRIM13 (RFP2) downregulation decreases tumour cell growth in multiple myeloma through inhibition of NF Kappa B pathway and proteasome activity

    PubMed Central

    Gatt, Moshe E; Takada, Kohichi; Mani, Mala; Lerner, Mikael; Pick, Marjorie; Hideshima, Teru; Carrasco, Daniel E.; Protopopov, Alexei; Ivanova, Elena; Sangfelt, Olle; Grandér, Dan; Barlogie, Bart; Shaughnessy, John D.; Anderson, Kenneth C.; Carrasco, Daniel R.

    2013-01-01

    Multiple myeloma (MM) is an incurable neoplasm caused by proliferation of malignant plasma cells in the bone marrow (BM). MM is characterized frequently by a complete or partial deletion of chromosome 13q14, seen in more than 50% of patients at diagnosis. Within this deleted region the tripartite motif containing 13 (TRIM13, also termed RFP2) gene product has been proposed to be a tumour suppressor gene (TSG). Here, we show that low expression levels of TRIM13 in MM are associated with chromosome 13q deletion and poor clinical outcome. We present a functional analysis of TRIM13 using a loss-of-function approach, and demonstrate that TRIM13 downregulation decreases tumour cell survival as well as cell cycle progression and proliferation of MM cells. In addition, we provide evidence for the involvement of TRIM13 downregulation in inhibiting the NF kappa B pathway and the activity of the 20S proteasome. Although this data does not support a role of TRIM13 as a TSG, it substantiates important roles of TRIM13 in MM tumour survival and proliferation, underscoring its potential role as a novel target for therapeutic intervention. PMID:23647456

  5. Polyamine aza-cyclic compounds demonstrate anti-proliferative activity in vitro but fail to control tumour growth in vivo.

    PubMed

    Wong, Pui Ee; Tetley, Laurence; Dufès, Christine; Chooi, Kar Wai; Bolton, Katherine; Schätzlein, Andreas G; Uchegbu, Ijeoma F

    2010-11-01

    Cationic polyamines such as the poly(propylenimine) dendrimers (DAB16) are anti-tumour agents (Dufes et al., 2005, Cancer Res 65:8079-8084). Their mechanism of action is poorly understood, but the lack of in vivo toxicity suggests cancer specificity. To explore this polyamine pharmacophore we cross-linked the aza-cyclic compound, hexacyclen, with 1,4-dibromobutane or 1,8-dibromooctane to yield the polyamines [poly(butylhexacyclen)--CL4] or [poly(octylhexacyclen)--CL8] respectively, both free of primary amines. We characterised the compounds and their respective nanoparticles and examined their interaction with the putative targets of the cationic polyamines: the cell membrane and DNA. Like DAB 16, CL4 and CL8 bind plasmid DNA and all three compounds interrupted the cell cycle of A431 epidermoid carcinoma cells in the S-phase. Additionally all three compounds disrupted erythrocyte membranes, with CL8 and DAB 16 being more active, in this respect, than CL4. CL4 (IC(50) =775.1 µg mL(-1)) and CL8 (IC(50) =8.4 µg mL(-1)), in a similar manner to DAB 16, were anti-proliferative against A431 cells; although unlike DAB 16, CL4 and CL8 were not tumouricidal against A431 xenografts in mice, indicating that primary amines may play an important role in the in vivo activity of DAB 16. PMID:20845462

  6. Active Targets For Capacitive Proximity Sensors

    NASA Technical Reports Server (NTRS)

    Jenstrom, Del T.; Mcconnell, Robert L.

    1994-01-01

    Lightweight, low-power active targets devised for use with improved capacitive proximity sensors described in "Capacitive Proximity Sensor Has Longer Range" (GSC-13377), and "Capacitive Proximity Sensors With Additional Driven Shields" (GSC-13475). Active targets are short-distance electrostatic beacons; they generate known alternating electro-static fields used for alignment and/or to measure distances.

  7. Water-soluble aluminium phthalocyanine-polymer conjugates for PDT: photodynamic activities and pharmacokinetics in tumour-bearing mice.

    PubMed

    Brasseur, N; Ouellet, R; La Madeleine, C; van Lier, J E

    1999-07-01

    The potential use of unsubstituted aluminium phthalocyanine (AlClPc) as a sensitizer for photodynamic therapy (PDT) of cancer has not been fully exploited in spite of its higher efficiency as compared to the sulphonated derivatives. This is largely due to the strong hydrophobic character of AlClPc which renders the material difficult to formulate for in vivo administration. We prepared two water-soluble derivatives of AlClPc by axial coordination of polyethyleneglycol (PEG, MW 2000) or polyvinylalcohol (PVA, MW 13,000-23,000) to the central aluminium ion. Their photodynamic activities were evaluated in vitro against the EMT-6 mouse mammary tumour cells and in vivo against the EMT-6 and the colon carcinoma Colo-26 tumours implanted intradermally in Balb/c mice. Pharmacokinetics were studied in the EMT-6 tumour-bearing mice. After 1 h incubation, the light dose required to kill 90% of cells (LD90) was at least three times less for AlClPc (Cremophor emulsion) as compared to AlPc-PEG and AlPc-PVA, while after 24 h incubation all three preparations were highly phototoxic. All three dye preparations induced complete EMT-6 tumour regression in 75-100% of animals at a low drug dose (0.25 micromol kg(-1)) following PDT (400 J cm(-2), 650-700 nm) at 24 h pi. Complete tumour regression in the Colo-26 tumour model was obtained in 30% of mice at a dose of 2 micromol kg(-1). In the non-cured animals, AlPc-PVA induced the most significant tumour growth delay. This dye showed a prolonged plasma half-life (6.8 h) as compared to AlClPc (2.6 h) and AlPc-PEG (23 min), lower retention by liver and spleen and higher tumour-to-skin and tumour-to-muscle ratios. Our data demonstrate that addition of hydrophilic axial ligands to AlPc, while modifying in vitro and in vivo kinetics, does not reduce the PDT efficiency of the parent molecule. Moreover, in the case of the polyvinylalcohol derivative, axial coordination confers advantageous pharmacokinetics to AlPc, which makes this

  8. Water-soluble aluminium phthalocyanine–polymer conjugates for PDT: photodynamic activities and pharmacokinetics in tumour-bearing mice

    PubMed Central

    Brasseur, N; Ouellet, R; Madeleine, C La; Lier, J E van

    1999-01-01

    The potential use of unsubstituted aluminium phthalocyanine (AlClPc) as a sensitizer for photodynamic therapy (PDT) of cancer has not been fully exploited in spite of its higher efficiency as compared to the sulphonated derivatives. This is largely due to the strong hydrophobic character of AlClPc which renders the material difficult to formulate for in vivo administration. We prepared two water-soluble derivatives of AlClPc by axial coordination of polyethyleneglycol (PEG, MW 2000) or polyvinylalcohol (PVA, MW 13 000–23 000) to the central aluminium ion. Their photodynamic activities were evaluated in vitro against the EMT-6 mouse mammary tumour cells and in vivo against the EMT-6 and the colon carcinoma Colo-26 tumours implanted intradermally in Balb/c mice. Pharmacokinetics were studied in the EMT-6 tumour-bearing mice. After 1 h incubation, the light dose required to kill 90% of cells (LD90) was at least three times less for AlClPc (Cremophor emulsion) as compared to AlPc–PEG and AlPc–PVA, while after 24 h incubation all three preparations were highly phototoxic. All three dye preparations induced complete EMT-6 tumour regression in 75–100% of animals at a low drug dose (0.25 μmol kg−1) following PDT (400 J cm−2, 650–700 nm) at 24 h pi. Complete tumour regression in the Colo-26 tumour model was obtained in 30% of mice at a dose of 2 μmol kg−1. In the non-cured animals, AlPc–PVA induced the most significant tumour growth delay. This dye showed a prolonged plasma half-life (6.8 h) as compared to AlClPc (2.6 h) and AlPc–PEG (23 min), lower retention by liver and spleen and higher tumour-to-skin and tumour-to-muscle ratios. Our data demonstrate that addition of hydrophilic axial ligands to AlPc, while modifying in vitro and in vivo kinetics, does not reduce the PDT efficiency of the parent molecule. Moreover, in the case of the polyvinylalcohol derivative, axial coordination confers advantageous pharmacokinetics to AlPc, which makes this

  9. The structure-dependent toxicity, pharmacokinetics and anti-tumour activity of HPMA copolymer conjugates in the treatment of solid tumours and leukaemia.

    PubMed

    Tomalova, Barbora; Sirova, Milada; Rossmann, Pavel; Pola, Robert; Strohalm, Jiri; Chytil, Petr; Cerny, Viktor; Tomala, Jakub; Kabesova, Martina; Rihova, Blanka; Ulbrich, Karel; Etrych, Tomas; Kovar, Marek

    2016-02-10

    Polymer drug carriers that are based on N-(2-hydroxypropyl)methacrylamide (HPMA) copolymers have been widely used in the development and synthesis of high-molecular-weight (HMW) drug delivery systems for cancer therapy. In this study, we compared linear (Mw ~27kDa, Rh ~4nm) and non-degradable star (Mw ~250kDa, Rh ~13nm) HPMA copolymer conjugates bearing anthracycline antibiotic doxorubicin (DOX) bound via pH-sensitive hydrazone bond. We determined the in vitro and in vivo toxicity of both conjugates and their maximum tolerated dose (MTD). We also compared their anti-tumour activity in mouse B-cell leukaemia (BCL1) and a mouse T-cell lymphoma (EL4) model. We found that MTD was higher for the linear conjugate (85mgDOX/kg) and lower for the star conjugate (22.5mgDOX/kg). An evaluation of the intestinal barrier integrity using FITC-dextran as a gut permeability tracer proved that no pathology was caused by the MTD of either conjugate. However, free DOX showed some damage to the gut barrier. The therapy of BCL1 leukaemia by both of the polymeric conjugates using the MTD or its fraction (i.e., equitoxic dosage) showed better results in the case of the star conjugate. On the other hand, treatment of EL4 lymphoma seemed to be more efficient when the linear conjugate was used. We suppose that the anti-cancer treatment of solid tumours and leukaemias requires different types of drug conjugates. We hypothesise that the most suitable HPMA copolymer-DOX conjugate for the treatment of solid tumours should have an HMW structure with increased Rh that would be stable for three to four days after the conjugate administration and then rapidly disintegrate in the short polymer chains, which are excretable from the body by glomerular filtration. On the other hand, the treatment of leukaemia requires a drug conjugate with a long circulation half-life. This would provide an active drug, whilst slowly degrading to excretable fragments. PMID:26708020

  10. FMLP- and TNF-stimulated monoclonal Lym-1 antibody-dependent lysis of B lymphoblastoid tumour targets by neutrophils.

    PubMed

    Ottonello, L; Morone, P; Mancini, M; Amelotti, M; Dapino, P; Dallegri, F

    1999-05-01

    Human neutrophils, incubated with Cr51-labelled B lymphoblastoid Raji cells in the presence of the anti-target monoclonal antibody (mAb) Lym-1 plus formyl-methionyl-leucyl-phenylalanine (FMLP) or tumour necrosis factor alpha (TNF-alpha), were found to induce significant C51 release, i.e. significant cytolysis. The lytic process was inhibited by mAb IV.3, specific for the Fcgamma receptor (FcgammaR) type II. The mAb 3G8, which reacts with FcgammaR type III, was ineffective. Moreover, the lysis was inhibited by the anti-CD18 mAb MEM-48. These data suggest that FMLP/Lym-1 as well as TNF-alpha/Lym-1 cytolytic systems strictly require FcgammaRII and CD18 integrins. As the lysis induced by TNF-alpha/Lym-1 was prevented by pertussis toxin (PT), PT-sensitive G-proteins are likely to intervene in post-FcgammaRII signal transduction. Both the FMLP- and the TNF-alpha-dependent systems were also found to be equally susceptible to inhibition by various inhibitors of kinases (genistein, staurosporin, 1-(5-isoquinolinnylsulphonyl)-2-methylpiperazine and wortmannin). On the contrary, an inhibitor of protein kinase C (bis-indolyl-maleimide, BIM) was effective only in the FMLP/Lym-1 cytolytic system. Therefore, it appears that signals delivered by FMLP or TNF-alpha, BIM-sensitive and insensitive respectively, converge and synergize with those from G-protein-coupled FcgammaRII and, probably, CD18-integrins to promote the expression of the neutrophil cytolytic potential. PMID:10408834

  11. FMLP- and TNF-stimulated monoclonal Lym-1 antibody-dependent lysis of B lymphoblastoid tumour targets by neutrophils

    PubMed Central

    Ottonello, L; Morone, P; Mancini, M; Amelotti, M; Dapino, P; Dallegri, F

    1999-01-01

    Human neutrophils, incubated with Cr51-labelled B lymphoblastoid Raji cells in the presence of the anti-target monoclonal antibody (mAb) Lym-1 plus formyl-methionyl-leucyl-phenylalanine (FMLP) or tumour necrosis factor alpha (TNF-α), were found to induce significant Cr51 release, i.e. significant cytolysis. The lytic process was inhibited by mAb IV.3, specific for the Fcγ receptor (FcγR) type II. The mAb 3G8, which reacts with FcγR type III, was ineffective. Moreover, the lysis was inhibited by the anti-CD18 mAb MEM-48. These data suggest that FMLP/Lym-1 as well as TNF-α/Lym-1 cytolytic systems strictly require FcγRII and CD18 integrins. As the lysis induced by TNF-α/Lym-1 was prevented by pertussis toxin (PT), PT-sensitive G-proteins are likely to intervene in post-FcγRII signal transduction. Both the FMLP- and the TNF-α-dependent systems were also found to be equally susceptible to inhibition by various inhibitors of kinases (genistein, staurosporin, 1-(5-isoquinolinnylsulphonyl)-2-methylpiperazine and wortmannin). On the contrary, an inhibitor of protein kinase C (bis-indolyl-maleimide, BIM) was effective only in the FMLP/Lym-1 cytolytic system. Therefore, it appears that signals delivered by FMLP or TNF-α, BIM-sensitive and insensitive respectively, converge and synergize with those from G-protein-coupled FcγRII and, probably, CD18-integrins to promote the expression of the neutrophil cytolytic potential. © 1999 Cancer Research Campaign PMID:10408834

  12. Activating Transcription Factor 3 regulates in part the enhanced tumour cell cytotoxicity of the histone deacetylase inhibitor M344 and cisplatin in combination

    PubMed Central

    2010-01-01

    Background Activating Transcription Factor (ATF) 3 is a key regulator of the cellular integrated stress response whose expression has also been correlated with pro-apoptotic activities in tumour cell models. Combination treatments with chemotherapeutic drugs, such as cisplatin, and histone deacetylase (HDAC) inhibitors have been demonstrated to enhance tumour cell cytotoxicity. We recently demonstrated a role for ATF3 in regulating cisplatin-induced apoptosis and others have shown that HDAC inhibition can also induce cellular stress. In this study, we evaluated the role of ATF3 in regulating the co-operative cytotoxicity of cisplatin in combination with an HDAC inhibitor. Results The HDAC inhibitor M344 induced ATF3 expression at the protein and mRNA level in a panel of human derived cancer cell lines as determined by Western blot and quantitative RT-PCR analyses. Combination treatment with M344 and cisplatin lead to increased induction of ATF3 compared with cisplatin alone. Utilizing the MTT cell viability assay, M344 treatments also enhanced the cytotoxic effects of cisplatin in these cancer cell lines. The mechanism of ATF3 induction by M344 was found to be independent of MAPKinase pathways and dependent on ATF4, a known regulator of ATF3 expression. ATF4 heterozygote (+/-) and knock out (-/-) mouse embryonic fibroblast (MEF) as well as chromatin immunoprecipitation (ChIP) assays were utilized in determining the mechanistic induction of ATF3 by M344. We also demonstrated that ATF3 regulates the enhanced cytotoxicity of M344 in combination with cisplatin as evidenced by attenuation of cytotoxicity in shRNAs targeting ATF3 expressing cells. Conclusion This study identifies the pro-apoptotic factor, ATF3 as a novel target of M344, as well as a mediator of the co-operative effects of cisplatin and M344 induced tumour cell cytotoxicity. PMID:20828393

  13. Profiling of Sox4-dependent transcriptome in skin links tumour suppression and adult stem cell activation.

    PubMed

    Foronda, Miguel; Morgado-Palacin, Lucia; Gómez-López, Gonzalo; Domínguez, Orlando; Pisano, David G; Blasco, Maria A

    2015-12-01

    Adult stem cells (ASCs) reside in specific niches in a quiescent state in adult mammals. Upon specific cues they become activated and respond by self-renewing and differentiating into newly generated specialised cells that ensure appropriate tissue fitness. ASC quiescence also serves as a tumour suppression mechanism by hampering cellular transformation and expansion (White AC et al., 2014). Some genes restricted to early embryonic development and adult stem cell niches are often potent modulators of stem cell quiescence, and derailed expression of these is commonly associated to cancer (Vervoort SJ et al., 2013). Among them, it has been shown that recommissioned Sox4 expression facilitates proliferation, survival and migration of malignant cells. By generating a conditional Knockout mouse model in stratified epithelia (Sox4 (cKO) mice), we demonstrated a delayed plucking-induced Anagen in the absence of Sox4. Skin global transcriptome analysis revealed a prominent defect in the induction of transcriptional networks that control hair follicle stem cell (HFSC) activation such as those regulated by Wnt/Ctnnb1, Shh, Myc or Sox9, cell cycle and DNA damage response-associated pathways. Besides, Sox4 (cKO) mice are resistant to skin carcinogenesis, thus linking Sox4 to both normal and pathological HFSC activation (Foronda M et al., 2014). Here we provide additional details on the analysis of Sox4-regulated transcriptome in Telogen and Anagen skin. The raw and processed microarray data is deposited in GEO under GSE58155. PMID:26697322

  14. Profiling of Sox4-dependent transcriptome in skin links tumour suppression and adult stem cell activation

    PubMed Central

    Foronda, Miguel; Morgado-Palacin, Lucia; Gómez-López, Gonzalo; Domínguez, Orlando; Pisano, David G.; Blasco, Maria A.

    2015-01-01

    Adult stem cells (ASCs) reside in specific niches in a quiescent state in adult mammals. Upon specific cues they become activated and respond by self-renewing and differentiating into newly generated specialised cells that ensure appropriate tissue fitness. ASC quiescence also serves as a tumour suppression mechanism by hampering cellular transformation and expansion (White AC et al., 2014). Some genes restricted to early embryonic development and adult stem cell niches are often potent modulators of stem cell quiescence, and derailed expression of these is commonly associated to cancer (Vervoort SJ et al., 2013). Among them, it has been shown that recommissioned Sox4 expression facilitates proliferation, survival and migration of malignant cells. By generating a conditional Knockout mouse model in stratified epithelia (Sox4cKO mice), we demonstrated a delayed plucking-induced Anagen in the absence of Sox4. Skin global transcriptome analysis revealed a prominent defect in the induction of transcriptional networks that control hair follicle stem cell (HFSC) activation such as those regulated by Wnt/Ctnnb1, Shh, Myc or Sox9, cell cycle and DNA damage response-associated pathways. Besides, Sox4cKO mice are resistant to skin carcinogenesis, thus linking Sox4 to both normal and pathological HFSC activation (Foronda M et al., 2014). Here we provide additional details on the analysis of Sox4-regulated transcriptome in Telogen and Anagen skin. The raw and processed microarray data is deposited in GEO under GSE58155. PMID:26697322

  15. Surgical implications of tumour immunology.

    PubMed Central

    Somers, S. S.

    1996-01-01

    The presence of immune infiltration of tumour deposits and the existence of effective in vitro anti-tumour immune responses would suggest the possibility of therapeutic manipulation against tumour cells. However, clinical immunotherapy has shown little promise as a cancer treatment. Numerous explanations for this inefficacy have been proposed, one of which involves the elaboration of immunosuppressive moieties from tumour cells. The results of studies presented below show that serum from patients with gastrointestinal and other tumours have immunosuppressive influences on normal lymphocytes. The degree of this in vitro inhibition is related to tumour 'bulk' and may reflect a systemic immunosuppressive influence of the tumour. Isolation and culture of lymphocytes from gastrointestinal tumour deposits demonstrated that these immune cells are functionally inert, suggesting the existence of an immunosuppressive tumour microenvironment. The isolation and partial purification of an immunosuppressive moiety from conditioned culture medium of a variety of human tumour cell lines further supports the hypothesis of tumour-mediated immunosuppression. A number of protein tumour cell products have been described with potent immunosuppressive properties. These include transforming growth factor-beta, interleukin-10, and the retroviral envelope protein p15E. The surgical implications of the proposed tumour-host immune relationship includes the hypothesis that clinically apparent disease may not be amenable to immune attack owing to tumour-mediated immune suppression. The use of immunostimulatory strategies as adjuvant perioperative therapy would seem a more effective environment for the activation of antitumour immune responses in the surgical patient. PMID:8678441

  16. Tumour shrinkage measured with first treatment evaluation under VEGF-targeted therapy as prognostic marker in metastatic renal cell carcinoma (mRCC)

    PubMed Central

    Seidel, C; Busch, J; Weikert, S; Steffens, S; Bokemeyer, C; Grünwald, V

    2013-01-01

    Background: The aim of our analysis is to further characterise the prognostic relevance of early tumour shrinkage (TS) during VEGF-targeted therapy in mRCC, in order to explore whether this could define a group of patients with long-term survivorship. Methods: A hundred patients were stratified into five subgroups according to their change of tumour size with first treatment evaluation: −100% to −60% −59% to −30% and −29% to 0% TS or gain of tumour size from 1% to 19% and ⩾20% or occurrence of new lesions (i.e., progressive disease). Results: The median PFS and OS were 10.4 months and 28.2 months, respectively. The median OS stratified according to the subgroups as described above was 77.4, 33.5, 26.9, 30.0 and 14.3 months, respectively. Multivariate analysis revealed early TS as a prognostic marker (P=0.021; HR 1.624). Conclusion: The extent of TS defines a small proportion of patients with an excellent prognosis. Larger studies are warranted to define the relationship of long-term survivorship and extent of TS with targeted therapies. PMID:24169357

  17. Chemical composition of Schinus molle essential oil and its cytotoxic activity on tumour cell lines.

    PubMed

    Díaz, Cecilia; Quesada, Silvia; Brenes, Oscar; Aguilar, Gilda; Cicció, José F

    2008-01-01

    The leaf essential oil hydrodistilled from Schinus molle grown in Costa Rica was characterised in terms of its chemical composition, antioxidant activity, ability to induce cytotoxicity and the mechanism of cell death involved in the process. As a result, 42 constituents, accounting for 97.2% of the total oil, were identified. The major constituents of the oil were beta-pinene and alpha-pinene. The antioxidant activity showed an IC(50) of 36.3 microg mL(-1). The essential oil was cytotoxic in several cell lines, showing that it is more effective on breast carcinoma and leukemic cell lines. The LD(50) for cytotoxicity at 48 h in K562 corresponded to 78.7 microg mL(-1), which was very similar to the LD(50) obtained when apoptosis was measured. The essential oil did not induce significant necrosis up to 200 microg mL(-1), which together with the former results indicate that apoptosis is the main mechanism of toxicity induced by S. molle essential oil in this cell line. In conclusion, the essential oil tested was weak antioxidant and induced cytotoxicity in different cell types by a mechanism related to apoptosis. It would be interesting to elucidate the role that different components of the oil play in the effect observed here, since some of them could have potential anti-tumoural effects, either alone or in combination. PMID:19023816

  18. Targeted Next-Generation Sequencing of Plasma DNA from Cancer Patients: Factors Influencing Consistency with Tumour DNA and Prospective Investigation of Its Utility for Diagnosis.

    PubMed

    Kaisaki, Pamela J; Cutts, Anthony; Popitsch, Niko; Camps, Carme; Pentony, Melissa M; Wilson, Gareth; Page, Suzanne; Kaur, Kulvinder; Vavoulis, Dimitris; Henderson, Shirley; Gupta, Avinash; Middleton, Mark R; Karydis, Ioannis; Talbot, Denis C; Schuh, Anna; Taylor, Jenny C

    2016-01-01

    Use of circulating tumour DNA (ctDNA) as a liquid biopsy has been proposed for potential identification and monitoring of solid tumours. We investigate a next-generation sequencing approach for mutation detection in ctDNA in two related studies using a targeted panel. The first study was retrospective, using blood samples taken from melanoma patients at diverse timepoints before or after treatment, aiming to evaluate correlation between mutations identified in biopsy and ctDNA, and to acquire a first impression of influencing factors. We found good concordance between ctDNA and tumour mutations of melanoma patients when blood samples were collected within one year of biopsy or before treatment. In contrast, when ctDNA was sequenced after targeted treatment in melanoma, mutations were no longer found in 9 out of 10 patients, suggesting the method might be useful for detecting treatment response. Building on these findings, we focused the second study on ctDNA obtained before biopsy in lung patients, i.e. when a tentative diagnosis of lung cancer had been made, but no treatment had started. The main objective of this prospective study was to evaluate use of ctDNA in diagnosis, investigating the concordance of biopsy and ctDNA-derived mutation detection. Here we also found positive correlation between diagnostic lung biopsy results and pre-biopsy ctDNA sequencing, providing support for using ctDNA as a cost-effective, non-invasive solution when the tumour is inaccessible or when biopsy poses significant risk to the patient. PMID:27626278

  19. Target activation by regulatory RNAs in bacteria

    PubMed Central

    Papenfort, Kai; Vanderpool, Carin K.

    2015-01-01

    Bacterial small regulatory RNAs (sRNAs) are commonly known to repress gene expression by base pairing to target mRNAs. In many cases, sRNAs base pair with and sequester mRNA ribosome-binding sites, resulting in translational repression and accelerated transcript decay. In contrast, a growing number of examples of translational activation and mRNA stabilization by sRNAs have now been documented. A given sRNA often employs a conserved region to interact with and regulate both repressed and activated targets. However, the mechanisms underlying activation differ substantially from repression. Base pairing resulting in target activation can involve sRNA interactions with the 5′ untranslated region (UTR), the coding sequence or the 3′ UTR of the target mRNAs. Frequently, the activities of protein factors such as cellular ribonucleases and the RNA chaperone Hfq are required for activation. Bacterial sRNAs, including those that function as activators, frequently control stress response pathways or virulence-associated functions required for immediate responses to changing environments. This review aims to summarize recent advances in knowledge regarding target mRNA activation by bacterial sRNAs, highlighting the molecular mechanisms and biological relevance of regulation. PMID:25934124

  20. Inhibition of indoleamine 2,3-dioxygenase activity enhances the anti-tumour effects of a Toll-like receptor 7 agonist in an established cancer model

    PubMed Central

    Ito, Hiroyasu; Ando, Tatsuya; Arioka, Yuko; Saito, Kuniaki; Seishima, Mitsuru

    2015-01-01

    Toll-like receptor (TLR) agonists have been shown to have anti-tumour activity in basic research and clinical studies. However, TLR agonist monotherapy does not sufficiently eliminate tumours. Activation of the innate immune response by TLR agonists is effective at driving adaptive immunity via interleukin-12 (IL-12) or IL-1, but is counteracted by the simultaneous induction of immunosuppressive cytokines and other molecules, including IL-10, transforming growth factor-β, and indoleamine 2,3-dioxygenase (IDO). In the present study, we evaluated the anti-cancer effect of the TLR7 agonist, imiquimod (IMQ), in the absence of IDO activity. The administration of IMQ in IDO knockout (KO) mice inoculated with tumour cells significantly suppressed tumour progression compared with that in wild-type (WT) mice, and improved the survival rate. Moreover, injection with IMQ enhanced the tumour antigen-specific T helper type 1 response in IDO-KO mice with tumours. Combination therapy with IMQ and an IDO inhibitor also significantly inhibited tumour growth. Our results indicated that the enhancement of IDO expression with TLR agonists in cancer treatment might impair host anti-tumour immunity while the inhibition of IDO could enhance the therapeutic efficacy of TLR agonists via the increase of T helper type 1 immune response. PMID:25322876

  1. Anti-tumour activity of two novel compounds in cisplatin-resistant testicular germ cell cancer

    PubMed Central

    Nitzsche, B; Gloesenkamp, C; Schrader, M; Hoffmann, B; Zengerling, F; Balabanov, S; Honecker, F; Höpfner, M

    2012-01-01

    Background: Resistance to cisplatin-based chemotherapy is associated with poor prognosis in testicular germ cell cancer, emphasising the need for new therapeutic approaches. In this respect, the therapeutic concept of anti-angiogenesis is of particular interest. In a previous study, we presented two novel anti-angiogenic compounds, HP-2 and HP-14, blocking the tyrosine kinase activity of angiogenic growth factor receptors, such as vascular endothelial growth factor receptor-2 (VEGFR-2), and related signalling pathways in testicular cancer. In this study, we investigated the efficacy of these new compounds in platinum-resistant testicular germ cell tumours (TGCTs), in vitro and in vivo. Methods and results: Drug-induced changes in cell proliferation of the cisplatin-sensitive TGCT cell line 2102EP and its cisplatin-resistant counterpart 2102EP-R, both expressing the VEGFR-2, were evaluated by crystal violet staining. Both compounds inhibited the growth of cisplatin-resistant TGCT cells in a dose-dependent manner. In combination experiments with cisplatin, HP-14 revealed additive growth-inhibitory effects in TGCT cells, irrespective of the level of cisplatin resistance. Anti-angiogenic effects of HP compounds were confirmed by tube formation assays with freshly isolated human umbilical vein endothelial cells. Using TGCT cells inoculated onto the chorioallantoic membrane of fertilised chicken eggs (chicken chorioallantoic membrane assay), the anti-angiogenic and anti-proliferative potency of the novel compounds was also demonstrated in vivo. Gene expression profiling revealed changes in the expression pattern of genes related to DNA damage detection and repair, as well as in chaperone function after treatment with both cisplatin and HP-14, alone or in combination. This suggests that HP-14 can revert the lost effectiveness of cisplatin in the resistant cells by altering the expression of critical genes. Conclusion: The novel compound HP-14 effectively inhibits the

  2. Optimisation of the purification process of a tumour-targeting antibody produced in N. benthamiana using vacuum-agroinfiltration.

    PubMed

    Lombardi, Raffaele; Villani, Maria Elena; Di Carli, Mariasole; Brunetti, Patrizia; Benvenuto, Eugenio; Donini, Marcello

    2010-12-01

    It was previously demonstrated that the tumour-targeting antibody mAb H10 can be transiently expressed and purified at high levels in Nicotiana benthamiana by using a vacuum-agroinfiltration system boosted by the use of a virus silencing suppressor protein. Scope of this work was to analyse different steps of protein extraction from agroinfiltrated leaves to optimise the purification process of the secretory mAb H10 providing new insights in the field of large-scale plant production. Two different extraction procedures (mechanical shearing/homogenisation and recovery of intercellular fluids -IFs-) were evaluated and compared in terms of purified antibody yields, antibody degradation and total phenolic compounds content. Mechanical grinding from fresh leaf tissues gave the highest purification yield (75 mg/kg Fresh Weight -75% intact tetrameric IgG-) and total phenolics concentration in the range of 420 μg/g FW. The second extraction procedure, based on the recovery of IFs, gave purification yields of 15-20 mg/kg FW (corresponding to 27% of total soluble protein) in which about 40% of purified protein is constituted by fully assembled IgG with a total phenolic compounds content reduced by one order of magnitude (21 μg/g FW). Despite a higher antibody degradation, purification from intercellular fluids demonstrated to be very promising since extraction procedures resulted extremely fast and amenable to scaling-up. Overall data highlight that different extraction procedures can dramatically affect the proteolytic degradation and quality of antibody purified from agroinfiltrated N. benthamiana leaves. Based on these results, we optimised a pilot-scale purification protocol using a two-step purification procedure from batches of fresh agroinfiltrated leaves (250 g) allowing purification of milligram quantities (average yield 40 mg/kg FW) of fully assembled and functional IgG with a 99.4% purity, free of phenolic and alkaloid compounds with low endotoxin levels

  3. Immunology of naturally transmissible tumours.

    PubMed

    Siddle, Hannah V; Kaufman, Jim

    2015-01-01

    Naturally transmissible tumours can emerge when a tumour cell gains the ability to pass as an infectious allograft between individuals. The ability of these tumours to colonize a new host and to cross histocompatibility barriers contradicts our understanding of the vertebrate immune response to allografts. Two naturally occurring contagious cancers are currently active in the animal kingdom, canine transmissible venereal tumour (CTVT), which spreads among dogs, and devil facial tumour disease (DFTD), among Tasmanian devils. CTVT are generally not fatal as a tumour-specific host immune response controls or clears the tumours after transmission and a period of growth. In contrast, the growth of DFTD tumours is not controlled by the Tasmanian devil's immune system and the disease causes close to 100% mortality, severely impacting the devil population. To avoid the immune response of the host both DFTD and CTVT use a variety of immune escape strategies that have similarities to many single organism tumours, including MHC loss and the expression of immunosuppressive cytokines. However, both tumours appear to have a complex interaction with the immune system of their respective host, which has evolved over the relatively long life of these tumours. The Tasmanian devil is struggling to survive with the burden of this disease and it is only with an understanding of how DFTD passes between individuals that a vaccine might be developed. Further, an understanding of how these tumours achieve natural transmissibility should provide insights into general mechanisms of immune escape that emerge during tumour evolution. PMID:25187312

  4. Immunology of naturally transmissible tumours

    PubMed Central

    Siddle, Hannah V; Kaufman, Jim

    2015-01-01

    Naturally transmissible tumours can emerge when a tumour cell gains the ability to pass as an infectious allograft between individuals. The ability of these tumours to colonize a new host and to cross histocompatibility barriers contradicts our understanding of the vertebrate immune response to allografts. Two naturally occurring contagious cancers are currently active in the animal kingdom, canine transmissible venereal tumour (CTVT), which spreads among dogs, and devil facial tumour disease (DFTD), among Tasmanian devils. CTVT are generally not fatal as a tumour-specific host immune response controls or clears the tumours after transmission and a period of growth. In contrast, the growth of DFTD tumours is not controlled by the Tasmanian devil's immune system and the disease causes close to 100% mortality, severely impacting the devil population. To avoid the immune response of the host both DFTD and CTVT use a variety of immune escape strategies that have similarities to many single organism tumours, including MHC loss and the expression of immunosuppressive cytokines. However, both tumours appear to have a complex interaction with the immune system of their respective host, which has evolved over the relatively long life of these tumours. The Tasmanian devil is struggling to survive with the burden of this disease and it is only with an understanding of how DFTD passes between individuals that a vaccine might be developed. Further, an understanding of how these tumours achieve natural transmissibility should provide insights into general mechanisms of immune escape that emerge during tumour evolution. PMID:25187312

  5. Therapeutic effect of interleukin 12 on mouse haemangiosarcomas is not associated with an increased anti-tumour cytotoxic T-lymphocyte activity.

    PubMed Central

    Vizler, C.; Rosato, A.; Calderazzo, F.; Quintieri, L.; Fruscella, P.; Wainstok de Calmanovici, R.; Mantovani, A.; Vecchi, A.; Zanovello, P.; Collavo, D.

    1998-01-01

    In syngeneic mice, the H5V polyoma middle-T oncogene-transformed endothelioma cell line induces Kaposi's sarcoma-like cavernous haemangiomas that regress transiently, probably because of an anti-tumour immune response, but eventually grow progressively and kill the host. To evaluate the generation of tumour-specific cytotoxic T lymphocytes (CTLs), spleen cells of tumour-bearing mice were restimulated with irradiated H5V cells in mixed leucocyte-tumour cell cultures. Tumour-specific CTLs were demonstrable only when low numbers of H5V stimulator cells were used (<1 H5V cell per 50 splenocytes). We found that H5V cells secrete immunosuppressive mediators because CTL generation was blocked when H5V cells culture supernatants were added to allogeneic mixed leucocyte cultures. As numerous tumour-derived immunosuppressive mediators may interfere with interleukin 12 (IL-12) production, we tested whether IL-12 treatment of the tumour-bearing mice would augment their immune response and thus suppress tumour growth. Indeed, IL-12 inhibited tumour growth and prevented mortality, but did not increase anti-H5V CTL generation either in vitro or in vivo. Moreover, the anti-tumour activity in IL-12-treated mice was abrogated by anti-interferon (IFN)-gamma monoclonal antibody (MAb) co-administration. These results strongly suggest that the anti-tumour effect of IL-12 is principally mediated by IFN-gamma release that in turn blocks H5V cell proliferation and induces the release of factors that suppress angiogenesis. PMID:9484826

  6. Anti-tumour promoting activity and antioxidant properties of girinimbine isolated from the stem bark of Murraya koenigii S.

    PubMed

    Kok, Yih Yih; Mooi, Lim Yang; Ahmad, Kartini; Sukari, Mohd Aspollah; Mat, Nashriyah; Rahmani, Mawardi; Ali, Abdul Manaf

    2012-01-01

    Girinimbine, a carbazole alkaloid isolated from the stem bark of Murraya koenigii was tested for the in vitro anti-tumour promoting and antioxidant activities. Anti-tumour promoting activity was determined by assaying the capability of this compound to inhibit the expression of early antigen of Epstein-Barr virus (EA-EBV) in Raji cells that was induced by the tumour promoter, phorbol 12-myristate 13-acetate. The concentration of this compound that gave an inhibition rate at fifty percent was 6.0 µg/mL and was not cytotoxic to the cells. Immunoblotting analysis of the expression of EA-EBV showed that girinimbine was able to suppress restricted early antigen (EA-R). However, diffused early antigen (EA-D) was partially suppressed when used at 32.0 µg/mL. Girinimbine exhibited a very strong antioxidant activity as compared to a-tocopherol and was able to inhibit superoxide generation in the 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced differentiated premyelocytic HL-60 cells more than 95%, when treated with the compound at 5.3 and 26.3 µg/mL, respectively. However girinimbine failed to scavenge the stable diphenyl picryl hydrazyl (DPPH)-free radical. PMID:22522395

  7. Antioxidant activity and cytotoxicity on tumour cells of the essential oil from Cedronella canariensis var. canariensis (L.) Webb & Berthel. (Lamiaceae).

    PubMed

    Zorzetto, Christian; Sánchez-Mateo, Candelaria C; Rabanal, Rosa M; Lupidi, Giulio; Bramucci, Massimo; Quassinti, Luana; Iannarelli, Romilde; Papa, Fabrizio; Maggi, Filippo

    2015-01-01

    Cedronella canariensis is a lemon-scented species of the family Lamiaceae endemic to the Canary Islands where it is used in the traditional medicine to prepare infusions or inhalations for anti-catarrhal, tonic, diuretic, hypoglycaemiant, hypotensive, anti-inflammatory and decongestant of the respiratory tract. In this work we investigated for the first time the antioxidant activity of the essential oil and its inhibitory effects on tumour cells (A375, MDA-MB-231, HCT 116) proliferation by DPPH, ABTS, FRAP and MTT assays, respectively. The oil, analysed by GC-ionisation flame detector and GC-MS, was characterised by pinocarvone (58.0%) and β-pinene (10.8%) as the major constituents, being typical of the chemotype 'canariensis'. Noteworthy was the cytotoxic activity of the oil against the tumour cells examined, with IC50 values of 4.3, 7.3 and 11.4 μg/mL on A375, MDA-MB-231 and HCT 116 tumour cells, respectively, as well as the scavenging activity against the ABTS radical (IC50 of 10.5 μg/mL). PMID:25560780

  8. Tumour growth inhibition and anti-metastatic activity of a mutated furin-resistant Semaphorin 3E isoform

    PubMed Central

    Casazza, Andrea; Kigel, Boaz; Maione, Federica; Capparuccia, Lorena; Kessler, Ofra; Giraudo, Enrico; Mazzone, Massimiliano; Neufeld, Gera; Tamagnone, Luca

    2012-01-01

    Secreted Semaphorin 3E (Sema3E) promotes cancer cell invasiveness and metastatic spreading. The pro-metastatic activity of Sema3E is due to its proteolytic fragment p61, capable of transactivating the oncogenic tyrosine kinase ErbB2 that associates with the Sema3E receptor PlexinD1 in cancer cells. Here, we show that a mutated, uncleavable variant of Sema3E (Uncl-Sema3E) binds to PlexinD1 like p61-Sema3E, but does not promote the association of PlexinD1 with ErbB2 nor activates the ensuing signalling cascade leading to metastatic spreading. Furthermore, Uncl-Sema3E competes with endogenous p61-Sema3E produced by tumour cells, thereby hampering their metastatic ability. Uncl-Sema3E also acts independently as a potent anti-angiogenic factor. It activates a PlexinD1-mediated signalling cascade in endothelial cells that leads to the inhibition of adhesion to extracellular matrix, directional migration and cell survival. The putative therapeutic potential of Uncl-Sema3E was validated in multiple orthotopic or spontaneous tumour models in vivo, where either local or systemic delivery of Uncl-Sema3E-reduced angiogenesis, growth and metastasis, even in the case of tumours refractory to treatment with a soluble vascular endothelial growth factor trap. In summary, we conclude that Uncl-Sema3E is a novel inhibitor of tumour angiogenesis and growth that concomitantly hampers metastatic spreading. PMID:22247010

  9. Video Guidance Sensors Using Remotely Activated Targets

    NASA Technical Reports Server (NTRS)

    Bryan, Thomas C.; Howard, Richard T.; Book, Michael L.

    2004-01-01

    Four updated video guidance sensor (VGS) systems have been proposed. As described in a previous NASA Tech Briefs article, a VGS system is an optoelectronic system that provides guidance for automated docking of two vehicles. The VGS provides relative position and attitude (6-DOF) information between the VGS and its target. In the original intended application, the two vehicles would be spacecraft, but the basic principles of design and operation of the system are applicable to aircraft, robots, objects maneuvered by cranes, or other objects that may be required to be aligned and brought together automatically or under remote control. In the first two of the four VGS systems as now proposed, the tracked vehicle would include active targets that would light up on command from the tracking vehicle, and a video camera on the tracking vehicle would be synchronized with, and would acquire images of, the active targets. The video camera would also acquire background images during the periods between target illuminations. The images would be digitized and the background images would be subtracted from the illuminated-target images. Then the position and orientation of the tracked vehicle relative to the tracking vehicle would be computed from the known geometric relationships among the positions of the targets in the image, the positions of the targets relative to each other and to the rest of the tracked vehicle, and the position and orientation of the video camera relative to the rest of the tracking vehicle. The major difference between the first two proposed systems and prior active-target VGS systems lies in the techniques for synchronizing the flashing of the active targets with the digitization and processing of image data. In the prior active-target VGS systems, synchronization was effected, variously, by use of either a wire connection or the Global Positioning System (GPS). In three of the proposed VGS systems, the synchronizing signal would be generated on, and

  10. The tumour antigen PRAME is a subunit of a Cul2 ubiquitin ligase and associates with active NFY promoters

    PubMed Central

    Costessi, Adalberto; Mahrour, Nawel; Tijchon, Esther; Stunnenberg, Rieka; Stoel, Marieke A; Jansen, Pascal W; Sela, Dotan; Martin-Brown, Skylar; Washburn, Michael P; Florens, Laurence; Conaway, Joan W; Conaway, Ronald C; Stunnenberg, Hendrik G

    2011-01-01

    The human tumour antigen PRAME (preferentially expressed antigen of melanoma) is frequently overexpressed in tumours. High PRAME levels correlate with poor clinical outcome of several cancers, but the mechanisms by which PRAME could be involved in tumourigenesis remain largely elusive. We applied protein-complex purification strategies and identified PRAME as a substrate recognition subunit of a Cullin2-based E3 ubiquitin ligase. PRAME can be recruited to DNA in vitro, and genome-wide chromatin immunoprecipitation experiments revealed that PRAME is specifically enriched at transcriptionally active promoters that are also bound by NFY and at enhancers. Our results are consistent with a role for the PRAME ubiquitin ligase complex in NFY-mediated transcriptional regulation. PMID:21822215

  11. Mode of action analysis for pesticide-induced rodent liver tumours involving activation of the constitutive androstane receptor: relevance to human cancer risk.

    PubMed

    Lake, Brian G; Price, Roger J; Osimitz, Thomas G

    2015-06-01

    A number of non-genotoxic chemicals, including some pesticides, have been shown to increase the incidence of liver tumours in rats and/or mice. Frameworks for analysing the modes of action (MOAs) by which chemicals produce liver tumours in rodents and the relevance of such tumour data for human risk assessment have now been established. One common MOA for rodent liver tumour formation by non-genotoxic chemicals involves activation of the constitutive androstane receptor (CAR). Key and associative events for a CAR-activation MOA include receptor activation, liver hypertrophy, induction of cytochrome P450 enzyme activities, increased replicative DNA synthesis, altered hepatic foci and liver tumours. While some effects of rodent CAR activators can be observed in human liver, a major species difference is that, unlike rodents, CAR activators do not increase replicative DNA synthesis in human hepatocytes. The CAR-activation MOA for rodent liver tumour formation is thus not plausible for humans, and hence such compounds do not pose a hepatocarcinogenic hazard for humans. PMID:25045103

  12. Active Targets for Experiments with Rare Isotopes

    NASA Astrophysics Data System (ADS)

    Wiedenhoever, Ingo

    2014-09-01

    Experimental studies of un-bound nuclear states and nuclear reaction rates relevant for astrophysical processes are an important area of research with rare isotope beams. Both topics require the development of specialized experimental methods to study resonant reactions. The so-called active target approach, where the target material becomes part of the detection process, promises to combine high yields from thicker targets and low background with high resolution. This presentation will describe the implementation of the active-target technique in the ANASEN detector, which was developed by researchers from Louisiana State University and Florida State University. ANASEN was used in a number of stable and rare iosotope experiments in α- and proton scattering, as well as (α , p) and (d , p) reactions at FSU's in-flight radioactive beam facility RESOLUT. ANASEN also was used to perform the first experiment, proton scattering off a 37K beam at the ReA3 facility. Another active-target detector with a very different approach is found in the Active Target Time-Projection Chamber, which was developed by a collaboration between researchers from MSU, the University of Notre Dame, Western Michigan University, LLNL, LBNL, and St. Mary's University (Canada). First experiments with an AT-TPC prototype have been reported. The talk will summarize the results from the first experiments with these systems, describe further development and future research projects. Experimental studies of un-bound nuclear states and nuclear reaction rates relevant for astrophysical processes are an important area of research with rare isotope beams. Both topics require the development of specialized experimental methods to study resonant reactions. The so-called active target approach, where the target material becomes part of the detection process, promises to combine high yields from thicker targets and low background with high resolution. This presentation will describe the implementation of the

  13. Raloxifene Inhibits NF-kB Pathway and Potentiates Anti-Tumour Activity of Cisplatin with Simultaneous Reduction in its Nephrotoxictiy.

    PubMed

    Jamdade, Vinayak Sudhir; Mundhe, Nitin A; Kumar, Parveen; Tadla, Venkatesh; Lahkar, Mangala

    2016-01-01

    Cisplatin induced nephrotoxicity is the chief obstacle in the use of cisplatin as chemotherapeutic agent. However, it remains as most widely employed anticancer agent to treat various solid tumours like head-neck, testicular, ovarian and mammary gland cancer. Raloxifene is claimed to be potent anti-inflammatory as well as anti-cancer agent. The present study was carried out to explore the effect of pre-treatment of raloxifene on cisplatin induced nephrotoxicity and its anti-tumour activity in 7, 12 dimethyl benz [a] anthracene induced mammary tumour in animal model. Renal damage was accessed by measuring serum level of creatinine, blood urea nitrogen and albumin whereas systemic inflammation was accessed by measuring level of pro-inflammatory cytokines like tumour necrosis factor alpha (TNF-α), interleukin 6 (IL-6), interleukin 10 (IL-10) and nuclear factor kappa B (NFκB). Moreover, assessment of tumour reduction was done by measuring tumour volume and percentage tumour reduction. A single dose of cisplatin (7.5 mg/kg) resulted in significant increase in serum creatinine, blood urea nitrogen, NF-kB, TNF-α and IL-6 levels along with decrease in albumin and IL-10 levels. However, there were no significant changes in raloxifene (8 mg/kg) treated group. Pre-treatment of raloxifene (8 mg/kg) caused marked decrease in serum creatinine, blood urea nitrogen, TNF-α and IL-6 levels whereas increase in albumin and IL-10 levels. However, pre-treatment of raloxifene showed maximum tumour reduction as compared to cisplatin and raloxifene treated groups. The present study demonstrates that raloxifene potentiates anti-tumour activity of cisplatin with simultaneous reduction in its nephrotoxicity, and this effect is attributed to its direct anti-inflammatory activity. PMID:26439246

  14. Activation of Mammalian target of rapamycin in canine mammary carcinomas: an immunohistochemical study.

    PubMed

    Delgado, L; Gärtner, F; Dias Pereira, P

    2015-01-01

    Mammalian target of rapamycin (mTOR) is a serine-threonine kinase involved in cell growth, proliferation and survival. Activation of mTOR has been reported in various tumour types, including human breast cancer; however, the expression of mTOR in canine mammary tumours has not been examined. In the present study, expression of the activated form of mTOR (phospho-mTOR [p-mTOR]) was examined immunohistochemically in five normal canine mammary glands, 45 canine mammary carcinomas and their corresponding metastatic lesions (n = 15). Phospho-mTOR was not expressed in normal canine mammary tissue, but cytoplasmic labelling was observed in 78% of canine mammary carcinomas. Two carcinomas had both cytoplasmic and nuclear labelling. No significant relationship was found between p-mTOR cytoplasmic expression and histological type or grading of carcinomas, degree of tubular formation, anisokaryosis, mitotic activity or lymph node metastasis. In all except one case, the expression pattern of p-mTOR in lymph node metastases was similar or decreased when compared with the primary lesion. The findings suggest that p-mTOR is involved in mammary carcinogenesis in dogs. However, p-mTOR cytoplasmic expression does not appear to be a prognostic indicator in canine mammary carcinomas, which may be related to its subcellular location in the neoplastic cells. Canine mammary tumours may provide a model for the development of innovative medical strategies involving mTOR inhibitors in human breast cancer. PMID:25670666

  15. Identification of C-terminal Hsp70-interacting protein as a mediator of tumour necrosis factor action in osteoblast differentiation by targeting osterix for degradation.

    PubMed

    Xie, Jianmin; Gu, Jieruo

    2015-08-01

    In patients with inflammatory arthritis, tumour necrosis factor (TNF)-α are overproduced in inflamed joints. This leads to local erosion of cartilage and bone, periarticular osteopenia, as well as osteoporosis. But less is known regarding the molecular mechanisms that mediate the effect of TNF-α on osteoblast function. The purpose of this study was to test that C terminus of Hsc70-interacting protein (CHIP) has a specific role in suppressing the osteogenic activity of osteoblasts under inflammatory conditions. C2C12, MC3T3-E1 and HEK293T cell lines were cultured and cotransfected with related plasmids. After transfection, the cells were cultured further in the presence or absence of murine TNF-α and subjected to real time RT-PCR, Western blot, Ubiquitination assay, Co-immunoprecipitation, Luciferase reporter assay, Small interfering RNAs and Mineralization assay. The expression levels of TNF-α-induced CHIP and Osx were examined by RT-PCR and Western blot analysis. Co-immunoprecipitation and ubiquitination assays revealed ubiquitinated Osx, confirmed that CHIP indeed interacted with Osx and identified K55 and K386 residues as the ubiquitination sites in Osx, Luciferase reporter assay and Small interfering RNAs examined whether TNF-α target the bone morphogenetic protein signalling through CHIP. We established stable cell lines with the overexpression of HA-CHIP, Mineralization assay and CHIP siRNA demonstrated the important roles of CHIP on osteoblast function in conditions in which TNF-α is overexpressed. We found that the K55 and K386 residues are ubiquitination site(s) in Osx, and that TNF-α inhibits osteoblast differentiation by promoting Osx degradation through up-regulation of E3 ubiquitin ligase CHIP in osteoblast. Thus, CHIP targets Osx for ubiquitination and degradation in osteoblasts after chronic exposure to TNF-α, and inhibition of CHIP expression in osteoblasts may be a new mechanism to limit inflammation-mediated osteoporosis by promoting their

  16. Release of soluble "blocking" and "suppressor" factors from normal lymphocytes treated with RNA from spleens of tumour-bearing mice.

    PubMed Central

    Pennline, K. J.; Evans, S. B.; Nawrocki, J. F.; Rees, J. C.; Johnson, C. S.; Vallera, D. A.; Dodd, M. C.

    1979-01-01

    RNA extracted from the spleens of tumour-bearing (TLRNA) and tumour-immune (ILRNA) mice was shown to transfer to normal lymphocytes (NL) the ability to produce factors that blocked specific tumour-cell cytotoxicity and mediated specific antibody-dependent cell cytotoxicity (ADCC). Aliquots of normal C3H mouse lymphocytes were treated with TLRNA or ILRNA and cultured in vitro in the absence of tumour antigen. Supernatants were collected at 24h intervals and tested in a microcytotoxicity assay for blocking and ADCC activities. Factors that inhibited tumour destruction by specifically sensitized lymphocytes at the level of both the tumour cells and effector cells were demonstrable in culture supernatants of NL pretreated with TLRNA (50 or 100 microgram/4 X 10(6) cells) but not ILRNA. However, treatment of NL with either RNA resulted in the production factors that mediated tumour-specific ADCC. Cytotoxicity testing and absorption studies of the tumour cell and a control cell (LM) indicated that factors mediating ADCC and blocking at the target-cell level were specific for the tumour. Suppressor activity at the effector-cell level was not absorbed by tumour cells and represents a separate and distinct mechanism of immunosuppression. These data indicate that RNA faithfully transfers "suppressive" as well as "positive" types of immune responses that have been reported previously for lymphocytes obtained directly from tumour-bearing and tumour-immune animals. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 PMID:313804

  17. Interfering with stem cell-specific gatekeeper functions controls tumour initiation and malignant progression of skin tumours

    PubMed Central

    Petersson, Monika; Reuter, Karen; Brylka, Heike; Kraus, Andreas; Schettina, Peter; Niemann, Catherin

    2015-01-01

    Epithelial cancer constitutes a major clinical challenge and molecular mechanisms underlying the process of tumour initiation are not well understood. Here we demonstrate that hair follicle bulge stem cells (SCs) give rise to well-differentiated sebaceous tumours and show that SCs are not only crucial in tumour initiation, but are also involved in tumour plasticity and heterogeneity. Our findings reveal that SC-specific expression of mutant Lef1, which mimics mutations found in human sebaceous tumours, drives sebaceous tumour formation. Mechanistically, we demonstrate that mutant Lef1 abolishes p53 activity in SCs. Intriguingly, mutant Lef1 induces DNA damage and interferes with SC-specific gatekeeper functions normally protecting against accumulations of DNA lesions and cell loss. Thus, normal control of SC proliferation is disrupted by mutant Lef1, thereby allowing uncontrolled propagation of tumour-initiating SCs. Collectively, these findings identify underlying molecular and cellular mechanisms of tumour-initiating events in tissue SCs providing a potential target for future therapeutic strategies. PMID:25608467

  18. Bp44mT: an orally active iron chelator of the thiosemicarbazone class with potent anti-tumour efficacy

    PubMed Central

    Yu, Y; Rahmanto, Y Suryo; Richardson, DR

    2012-01-01

    BACKGROUND AND PURPOSE Our previous studies demonstrated that a thiosemicarbazone iron chelator (di-2-pyridylketone-4,4-dimethyl-3-thiosemicarbazone; Dp44mT) possesses potent and selective anti-cancer activity but led to cardiotoxicity at non-optimal doses. In this study, we examined the in vivo anti-tumour efficacy and tolerability of a new-generation 2-benzoylpyridine thiosemicarbazone iron chelator (2-benzoylpyridine-4,4-dimethyl-3-thiosemicarbazone; Bp44mT) administered via the oral or i.v. routes. EXPERIMENTAL APPROACH BpT chelators were tested in vitro against human lung cancer cells (DMS-53) and in vivo in DMS-53 tumour xenografts in mice. The toxicity of Bp44mT in vivo and its effects on the expression of iron-regulated molecules involved in growth and cell cycle control were investigated. KEY RESULTS Administration of Bp44mT by either route resulted in marked dose-dependent inhibition of tumour growth. When administered at 50 mg·kg−1 via oral gavage three times per week for 23 days, the net xenograft growth was inhibited by 75%, compared with vehicle-treated mice. Toxicological examination showed reversible alterations including slight reduction of RBC count, with a decrease of liver and splenic iron levels, which confirmed iron chelation in vivo. Importantly, in contrast to Dp44mT, the chelator-treated mice did not show cardiac histological abnormalities. There was also no significant weight loss in mice, suggesting oral administration of Bp44mT was well tolerated. CONCLUSIONS AND IMPLICATIONS This is the first study to show that Bp44mT can be given orally with potent anti-tumour efficacy. Oral administration of a novel and effective chemotherapeutic agent provides the benefits of convenience for chronic dosing regimens. PMID:21658021

  19. Targeted activation in deterministic and stochastic systems

    NASA Astrophysics Data System (ADS)

    Eisenhower, Bryan; Mezić, Igor

    2010-02-01

    Metastable escape is ubiquitous in many physical systems and is becoming a concern in engineering design as these designs (e.g., swarms of vehicles, coupled building energetics, nanoengineering, etc.) become more inspired by dynamics of biological, molecular and other natural systems. In light of this, we study a chain of coupled bistable oscillators which has two global conformations and we investigate how specialized or targeted disturbance is funneled in an inverse energy cascade and ultimately influences the transition process between the conformations. We derive a multiphase averaged approximation to these dynamics which illustrates the influence of actions in modal coordinates on the coarse behavior of this process. An activation condition that predicts how the disturbance influences the rate of transition is then derived. The prediction tools are derived for deterministic dynamics and we also present analogous behavior in the stochastic setting and show a divergence from Kramers activation behavior under targeted activation conditions.

  20. Uncaria tomentosa exerts extensive anti-neoplastic effects against the Walker-256 tumour by modulating oxidative stress and not by alkaloid activity.

    PubMed

    Dreifuss, Arturo Alejandro; Bastos-Pereira, Amanda Leite; Fabossi, Isabella Aviles; Lívero, Francislaine Aparecida Dos Reis; Stolf, Aline Maria; Alves de Souza, Carlos Eduardo; Gomes, Liana de Oliveira; Constantin, Rodrigo Polimeni; Furman, Aline Emmer Ferreira; Strapasson, Regiane Lauriano Batista; Teixeira, Simone; Zampronio, Aleksander Roberto; Muscará, Marcelo Nicolás; Stefanello, Maria Elida Alves; Acco, Alexandra

    2013-01-01

    This study aimed to compare the anti-neoplastic effects of an Uncaria tomentosa (UT) brute hydroethanolic (BHE) extract with those of two fractions derived from it. These fractions are choroformic (CHCl3) and n-butanolic (BuOH), rich in pentacyclic oxindole alkaloids (POA) and antioxidant substances, respectively. The cancer model was the subcutaneous inoculation of Walker-256 tumour cells in the pelvic limb of male Wistar rat. Subsequently to the inoculation, gavage with BHE extract (50 mg.kg(-1)) or its fractions (as per the yield of the fractioning process) or vehicle (Control) was performed during 14 days. Baseline values, corresponding to individuals without tumour or treatment with UT, were also included. After treatment, tumour volume and mass, plasma biochemistry, oxidative stress in liver and tumour, TNF-α level in liver and tumour homogenates, and survival rates were analysed. Both the BHE extract and its BuOH fraction successfully reduced tumour weight and volume, and modulated anti-oxidant systems. The hepatic TNF-α level indicated a greater effect from the BHE extract as compared to its BuOH fraction. Importantly, both the BHE extract and its BuOH fraction increased the survival time of the tumour-bearing animals. Inversely, the CHCl3 fraction was ineffective. These data represent an in vivo demonstration of the importance of the modulation of oxidative stress as part of the anti-neoplastic activity of UT, as well as constitute evidence of the lack of activity of isolated POAs in the primary tumour of this tumour lineage. These effects are possibly resulting from a synergic combination of substances, most of them with antioxidant properties. PMID:23408945

  1. An Approach to Breast Cancer Immunotherapy: The Apoptotic Activity of Recombinant Anti-Interleukin-6 Monoclonal Antibodies in Intact Tumour Microenvironment of Breast Carcinoma.

    PubMed

    Abou-Shousha, S; Moaaz, M; Sheta, M; Motawea, M A

    2016-06-01

    Current work is one of our comprehensive preclinical studies, a new approach to breast cancer (BC) immunotherapy through induction of tumour cell apoptosis. Tumour growth is not just a result of uncontrolled cell proliferation but also of reduced apoptosis. High levels of interleukin-6 (IL-6) are associated with metastatic BC and correlated with poor survival as it promotes growth of tumour-initiating cells during early tumorigenesis protecting these cells from apoptosis. Therefore, this study aims at investigating the potential of anti-IL-6 monoclonal antibodies to suppress IL-6 proliferative/anti-apoptotic activities in intact tumour microenvironment of BC. Fresh sterile tumour and normal breast tissue specimens were taken from 50 female Egyptian patients with BC undergoing radical mastectomy. A unique tissue culture system designed to provide cells of each intact tumour/normal tissue sample with its proper microenvironment either supplemented or not with anti-IL-6 monoclonal antibodies. To evaluate the apoptotic activity of anti-IL-6 as a novel candidate for BC treatment strategy, we compared its effects with those obtained using tumour necrosis-related apoptosis-inducing ligand TRAIL as an established apoptotic agent. Our results revealed that levels of either anti-IL-6- or TRAIL-induced apoptosis in the tumour or normal tissue cultures were significantly higher than those in their corresponding untreated ones (P < 0.001). No statistically significant differences have been found between apoptosis levels induced by anti-IL-6 monoclonal antibodies and those induced by TRAIL. Recombinant anti-IL-6 monoclonal antibodies could represent a novel effective element of immunotherapeutic treatment strategy for BC. The selectivity and anti-apoptotic potential of anti-IL-6 is highly hopeful in IL-6- abundant BC tumour microenvironment. PMID:26971879

  2. Uncaria tomentosa Exerts Extensive Anti-Neoplastic Effects against the Walker-256 Tumour by Modulating Oxidative Stress and Not by Alkaloid Activity

    PubMed Central

    Dreifuss, Arturo Alejandro; Bastos-Pereira, Amanda Leite; Fabossi, Isabella Aviles; Lívero, Francislaine Aparecida dos Reis; Stolf, Aline Maria; Alves de Souza, Carlos Eduardo; Gomes, Liana de Oliveira; Constantin, Rodrigo Polimeni; Furman, Aline Emmer Ferreira; Strapasson, Regiane Lauriano Batista; Teixeira, Simone; Zampronio, Aleksander Roberto; Muscará, Marcelo Nicolás; Stefanello, Maria Elida Alves; Acco, Alexandra

    2013-01-01

    This study aimed to compare the anti-neoplastic effects of an Uncaria tomentosa (UT) brute hydroethanolic (BHE) extract with those of two fractions derived from it. These fractions are choroformic (CHCl3) and n-butanolic (BuOH), rich in pentacyclic oxindole alkaloids (POA) and antioxidant substances, respectively. The cancer model was the subcutaneous inoculation of Walker-256 tumour cells in the pelvic limb of male Wistar rat. Subsequently to the inoculation, gavage with BHE extract (50 mg.kg−1) or its fractions (as per the yield of the fractioning process) or vehicle (Control) was performed during 14 days. Baseline values, corresponding to individuals without tumour or treatment with UT, were also included. After treatment, tumour volume and mass, plasma biochemistry, oxidative stress in liver and tumour, TNF-α level in liver and tumour homogenates, and survival rates were analysed. Both the BHE extract and its BuOH fraction successfully reduced tumour weight and volume, and modulated anti-oxidant systems. The hepatic TNF-α level indicated a greater effect from the BHE extract as compared to its BuOH fraction. Importantly, both the BHE extract and its BuOH fraction increased the survival time of the tumour-bearing animals. Inversely, the CHCl3 fraction was ineffective. These data represent an in vivo demonstration of the importance of the modulation of oxidative stress as part of the anti-neoplastic activity of UT, as well as constitute evidence of the lack of activity of isolated POAs in the primary tumour of this tumour lineage. These effects are possibly resulting from a synergic combination of substances, most of them with antioxidant properties. PMID:23408945

  3. MicroRNA-497 targets insulin-like growth factor 1 receptor and has a tumour suppressive role in human colorectal cancer

    PubMed Central

    Guo, S T; Jiang, C C; Wang, G P; Li, Y P; Wang, C Y; Guo, X Y; Yang, R H; Feng, Y; Wang, F H; Tseng, H-Y; Thorne, R F; Jin, L; Zhang, X D

    2013-01-01

    Past studies have shown that amplified insulin-like growth factor 1 (IGF1)/IGF1 receptor (IGF1-R) signalling has an important role in colorectal cancer (CRC) development, progression and resistance to treatment. In this report, we demonstrate that downregulation of microRNA-497 (miR-497) as a result of DNA copy number reduction is involved in upregulation of IGF1-R in CRC cells. MiR-497 and miR-195 of the miR-15/16/195/424/497 family that share the same 3′ untranslated region (3′UTR) binding seed sequence and are predicted to target IGF1-R were concurrently downregulated in the majority of CRC tissues relative to paired adjacent normal mucosa. However, only overexpression of miR-497 led to suppression of the IGF1-R 3′UTR activity and downregulation of the endogenous IGF1-R protein in CRC cells. This was associated with inhibition of cell survival, proliferation and invasion, and increased sensitivity to apoptosis induced by various stimuli including the chemotherapeutic drugs cisplatin and 5-fluorouracil, and the death ligand tumour necrosis factor-related apoptosis-inducing ligand. The biological effect of miR-497 on CRC cells was largely mediated by inhibition of phosphatidylinositol 3-kinase/Akt signalling, as overexpression of an active form of Akt reversed its impact on cell survival and proliferation, recapitulating the effect of overexpression of IGF1-R. Downregulation of miR-497 and miR-195 appeared to associate with copy number loss of a segment of chromosome 17p13.1, where these miRs are located at proximity. Similarly to miR-195, the members of the same miR family, miR-424 that was upregulated, and miR-15a, miR-15b and miR-16 that were unaltered in expression in CRC tissues compared with paired adjacent normal mucosa, did not appear to have a role in regulating the expression of IGF1-R. Taken together, these results identify downregulation of miR-497 as an important mechanism of upregulation of IGF1-R in CRC cells that contributes to malignancy of

  4. Tumour endothelial cells in high metastatic tumours promote metastasis via epigenetic dysregulation of biglycan

    PubMed Central

    Maishi, Nako; Ohba, Yusuke; Akiyama, Kosuke; Ohga, Noritaka; Hamada, Jun-ichi; Nagao-Kitamoto, Hiroko; Alam, Mohammad Towfik; Yamamoto, Kazuyuki; Kawamoto, Taisuke; Inoue, Nobuo; Taketomi, Akinobu; Shindoh, Masanobu; Hida, Yasuhiro; Hida, Kyoko

    2016-01-01

    Tumour blood vessels are gateways for distant metastasis. Recent studies have revealed that tumour endothelial cells (TECs) demonstrate distinct phenotypes from their normal counterparts. We have demonstrated that features of TECs are different depending on tumour malignancy, suggesting that TECs communicate with surrounding tumour cells. However, the contribution of TECs to metastasis has not been elucidated. Here, we show that TECs actively promote tumour metastasis through a bidirectional interaction between tumour cells and TECs. Co-implantation of TECs isolated from highly metastatic tumours accelerated lung metastases of low metastatic tumours. Biglycan, a small leucine-rich repeat proteoglycan secreted from TECs, activated tumour cell migration via nuclear factor-κB and extracellular signal–regulated kinase 1/2. Biglycan expression was upregulated by DNA demethylation in TECs. Collectively, our results demonstrate that TECs are altered in their microenvironment and, in turn, instigate tumour cells to metastasize, which is a novel mechanism for tumour metastasis. PMID:27295191

  5. Tumour endothelial cells in high metastatic tumours promote metastasis via epigenetic dysregulation of biglycan.

    PubMed

    Maishi, Nako; Ohba, Yusuke; Akiyama, Kosuke; Ohga, Noritaka; Hamada, Jun-Ichi; Nagao-Kitamoto, Hiroko; Alam, Mohammad Towfik; Yamamoto, Kazuyuki; Kawamoto, Taisuke; Inoue, Nobuo; Taketomi, Akinobu; Shindoh, Masanobu; Hida, Yasuhiro; Hida, Kyoko

    2016-01-01

    Tumour blood vessels are gateways for distant metastasis. Recent studies have revealed that tumour endothelial cells (TECs) demonstrate distinct phenotypes from their normal counterparts. We have demonstrated that features of TECs are different depending on tumour malignancy, suggesting that TECs communicate with surrounding tumour cells. However, the contribution of TECs to metastasis has not been elucidated. Here, we show that TECs actively promote tumour metastasis through a bidirectional interaction between tumour cells and TECs. Co-implantation of TECs isolated from highly metastatic tumours accelerated lung metastases of low metastatic tumours. Biglycan, a small leucine-rich repeat proteoglycan secreted from TECs, activated tumour cell migration via nuclear factor-κB and extracellular signal-regulated kinase 1/2. Biglycan expression was upregulated by DNA demethylation in TECs. Collectively, our results demonstrate that TECs are altered in their microenvironment and, in turn, instigate tumour cells to metastasize, which is a novel mechanism for tumour metastasis. PMID:27295191

  6. Activated hedgehog pathway is a potential target for pharmacological intervention in biliary tract cancer.

    PubMed

    Kiesslich, Tobias; Mayr, Christian; Wachter, Julia; Bach, Doris; Fuereder, Julia; Wagner, Andrej; Alinger, Beate; Pichler, Martin; Di Fazio, Pietro; Ocker, Matthias; Berr, Frieder; Neureiter, Daniel

    2014-11-01

    Hedgehog (Hh) signalling contributes to carcinogenesis and represents a valid druggable target in human cancers, possibly also in biliary tract cancer (BTC). We analysed the expression of Hh components in BTC using eight heterogeneously differentiated cell lines, xenograft tumours and a human tissue microarray. The dose-, time- and cell line-dependent effects of two Hh inhibitors (cyclopamine and Gant-61) were analysed in vitro for survival, apoptosis, cell cycle distribution and possible synergism with conventional chemotherapeutic agents. In human BTC samples, the sonic Hh ligand and the Gli1 transcription factor showed increased expression in tumours compared to normal adjacent tissue and were significantly associated with high tumour grade and positive lymph node status. In BTC cell lines, we could confirm the Hh component expression at varying extent within the employed cell lines in vitro and in vivo indicating non-canonical signalling. Both Hh inhibitors showed dose-dependent cytotoxicity above 5 µM with a stronger effect for Gant-61 inducing apoptosis whereas cyclopamine rather inhibited proliferation. Cytotoxicity was associated with low cytokeratin expression and higher mesenchymal marker expression such as vimentin. Additionally, drug combinations of Gant-61 with conventional chemotherapy (cisplatin) exerted synergistic effects. In conclusion, Hh pathway is significantly activated in human BTC tissue compared to normal adjacent tissue. The current data demonstrate for the first time an effective anticancer activity of especially Gant-61 in BTC and suggest second generation Hh pathway inhibitors as a potential novel treatment strategy in BTC. PMID:25064451

  7. Gastrointestinal stromal tumour.

    PubMed

    Joensuu, Heikki; Hohenberger, Peter; Corless, Christopher L

    2013-09-14

    Gastrointestinal stromal tumours (GISTs) are mesenchymal neoplasms that arise in the gastrointestinal tract, usually in the stomach or the small intestine and rarely elsewhere in the abdomen. They can occur at any age, the median age being 60-65 years, and typically cause bleeding, anaemia, and pain. GISTs have variable malignant potential, ranging from small lesions with a benign behaviour to fatal sarcomas. Most tumours stain positively for the mast/stem cell growth factor receptor KIT and anoctamin 1 and harbour a kinase-activating mutation in either KIT or PDGFRA. Tumours without such mutations could have alterations in genes of the succinate dehydrogenase complex or in BRAF, or rarely RAS family genes. About 60% of patients are cured by surgery. Adjuvant treatment with imatinib is recommended for patients with a substantial risk of recurrence, if the tumour has an imatinib-sensitive mutation. Tyrosine kinase inhibitors substantially improve survival in advanced disease, but secondary drug resistance is common. PMID:23623056

  8. Designing an Active Target Test Projection Chamber

    NASA Astrophysics Data System (ADS)

    Koci, James; Tan Ahn Collaboration, Dr.; Nicolas Dixneuf Collaboration

    2015-10-01

    The development of instrumentation in nuclear physics is crucial for advancing our ability to measure the properties of exotic nuclei. One limitation of the use of exotic nuclei in experiment is their very low production intensities. Recently, detectors, called active-target dectectors, have been developed to address this issue. Active-target detectors use a gas medium to image charged-particle tracks that are emitted in nuclear reactions. Last semester, I designed a vacuum chamber to be used in developing Micro-Pattern Gas detectors that will upgrade the capabilities of an active-target detector called the Prototype AT-TPC. With the exterior of the chamber complete, I have now been using an electric field modeling program, Garfield, developed by CERN to design a field cage to be placed within the vacuum chamber. The field cage will be a box-like apparatus consisting of two parallel metal plates connected with a resistor chain and attached to wires wrapped between them. The cage will provide a uniform electric field within the chamber to drift electrons from nuclear reactions down to the detector in the bottom of the chamber. These signals are then amplified by a proportional counter, and the data is sent to a computer. For the long term, we would like to incorporate a Micro-Pattern Gas Detectors in the interior of the chamber and eventually use the AT-TPC to examine various nuclei. Dr. Ahn is my advising professor.

  9. Clinical features of gastroenteropancreatic tumours

    PubMed Central

    Czarnywojtek, Agata; Bączyk, Maciej; Ziemnicka, Katarzyna; Fischbach, Jakub; Wrotkowska, Elżbieta; Ruchała, Marek

    2015-01-01

    Gastroenteropancreatic (GEP) endocrine tumours (carcinoids and pancreatic islet cell tumours) are composed of multipotent neuroendocrine cells that exhibit a unique ability to produce, store, and secrete biologically active substances and cause distinct clinical syndromes. The classification of GEP tumours as functioning or non-functioning is based on the presence of symptoms that accompany these syndromes secondary to the secretion of hormones, neuropeptides and/or neurotransmitters (functioning tumours). Non-functioning tumours are considered to be neoplasms of neuroendocrine differentiation that are not associated with obvious symptoms attributed to the hypersecretion of metabolically active substances. However, a number of these tumours are either capable of producing low levels of such substances, which can be detected by immunohistochemistry but are insufficient to cause symptoms related to a clinical syndrome, or alternatively, they may secrete substances that are either metabolically inactive or inappropriately processed. In some cases, GEP tumours are not associated with the production of any hormone or neurotransmitter. Both functioning and non-functioning tumours can also produce symptoms due to mass effects compressing vital surrounding structures. Gastroenteropancreatic tumours are usually classified further according to the anatomic site of origin: foregut (including respiratory tract, thymus, stomach, duodenum, and pancreas), midgut (including small intestine, appendix, and right colon), and hindgut (including transverse colon, sigmoid, and rectum). Within these subgroups the biological and clinical characteristics of the tumours vary considerably, but this classification is still in use because a significant number of previous studies, mainly observational, have used it extensively. PMID:26516377

  10. Production of a tumour-targeting antibody with a human-compatible glycosylation profile in N. benthamiana hairy root cultures.

    PubMed

    Lonoce, Chiara; Salem, Reda; Marusic, Carla; Jutras, Philippe V; Scaloni, Andrea; Salzano, Anna Maria; Lucretti, Sergio; Steinkellner, Herta; Benvenuto, Eugenio; Donini, Marcello

    2016-09-01

    Hairy root (HR) cultures derived from Agrobacterium rhizogenes transformation of plant tissues are an advantageous biotechnological manufacturing platform due to the accumulation of recombinant proteins in an otherwise largely protein free culture medium. In this context, HRs descending from transgenic Nicotiana tabacum plants were successfully used for the production of several functional mAbs with plant-type glycans. Here, we expressed the tumor-targeting monoclonal antibody mAb H10 in HRs obtained either by infecting a transgenic N. tabacum line expressing H10 with A. rhizogenes or a glyco-engineered N. benthamiana line (ΔXTFT) with recombinant A. rhizogenes carrying mAb H10 heavy and light chain cDNAs. Selected HR clones derived from both plants accumulated mAb H10 in the culture medium with similar yields (2-3 mg/L). N-glycosylation profiles of antibodies purified from HR supernatant revealed the presence of plant-typical complex structures for N. tabacum-derived mAb H10 and of GnGn structures lacking xylose and fucose for the ΔXTFT-derived counterpart. Both antibody glyco-formats exhibited comparable antigen binding activities. Collectively, these data demonstrate that the co-infection of ΔXTFT Nicotiana benthamiana with recombinant A. rhizogenes is an efficient procedure for the generation of stable HR cultures expressing the tumor-targeting mAb H10 with a human-compatible glycosylation profile, thus representing an important step towards the exploitation of root cultures for the production of 'next generation' human therapeutic antibodies. PMID:27313150

  11. HPV vaccine stimulates cytotoxic activity of killer dendritic cells and natural killer cells against HPV-positive tumour cells

    PubMed Central

    Van den Bergh, Johan M J; Guerti, Khadija; Willemen, Yannick; Lion, Eva; Cools, Nathalie; Goossens, Herman; Vorsters, Alex; Van Tendeloo, Viggo F I; Anguille, Sébastien; Van Damme, Pierre; Smits, Evelien L J M

    2014-01-01

    Cervarix™ is approved as a preventive vaccine against infection with the human papillomavirus (HPV) strains 16 and 18, which are causally related to the development of cervical cancer. We are the first to investigate in vitro the effects of this HPV vaccine on interleukin (IL)-15 dendritic cells (DC) as proxy of a naturally occurring subset of blood DC, and natural killer (NK) cells, two innate immune cell types that play an important role in antitumour immunity. Our results show that exposure of IL-15 DC to the HPV vaccine results in increased expression of phenotypic maturation markers, pro-inflammatory cytokine production and cytotoxic activity against HPV-positive tumour cells. These effects are mediated by the vaccine adjuvant, partly through Toll-like receptor 4 activation. Next, we demonstrate that vaccine-exposed IL-15 DC in turn induce phenotypic activation of NK cells, resulting in a synergistic cytotoxic action against HPV-infected tumour cells. Our study thus identifies a novel mode of action of the HPV vaccine in boosting innate immunity, including killing of HPV-infected cells by DC and NK cells. PMID:24979331

  12. Dihydro-β-agarofuran sesquiterpenes from celastraceae species as anti-tumour-promoting agents: Structure-activity relationship.

    PubMed

    Núñez, Marvin J; Jiménez, Ignacio A; Mendoza, Cristina R; Chavez-Sifontes, Marvin; Martinez, Morena L; Ichiishi, Eiichiro; Tokuda, Ryo; Tokuda, Harukuni; Bazzocchi, Isabel L

    2016-03-23

    Inhibition of tumour promotion in multistage chemical carcinogenesis is considered a promising strategy for cancer chemoprevention. In an ongoing investigation of bioactive secondary metabolites from Celastraceae species, five new dihydro-β-agarofuran sesquiterpenes (1-5), named Chiapens A-E, and seventeen known ones, were isolated from Maytenus chiapensis. Their structures were elucidated by extensive NMR spectroscopic and mass spectrometric techniques, and their absolute configurations were determined by circular dichroism studies, chemical correlations and biogenic means. The isolated compounds, along with twenty known sesquiterpenes, previously isolated from Zinowiewia costaricensis, have been tested for their inhibitory effects on Epstein-Barr virus early antigen (EBV-EA) activation induced by 12-O-tetradecanoylphorpol-13-acetate (TPA). Thirty three compounds from this series showed stronger effects than that of β-carotene, the reference inhibitor. The structure-activity relationship (SAR) analysis revealed that the type of substituent, in particular at the C-1 position of the sesquiterpene scaffold, was able to modulate the anti-tumour promoting activity. Compounds 3, 6, and 33 showed significant effects in an in vivo two-stage mouse-skin carcinogenesis model. PMID:26854381

  13. Metabonomic analysis of ovarian tumour cyst fluid by proton nuclear magnetic resonance spectroscopy.

    PubMed

    Kyriakides, Michael; Rama, Nona; Sidhu, Jasmin; Gabra, Hani; Keun, Hector C; El-Bahrawy, Mona

    2016-02-01

    The majority of ovarian tumours are of the epithelial type, which can be sub classified as benign, borderline or malignant. Epithelial tumours usually have cystic spaces filled with cyst fluid, the metabolic profile of which reflects the metabolic activity of the tumour cells, due to their close proximity. The approach of metabonomics using 1H-NMR spectroscopy was employed to characterize the metabolic profiles of ovarian cyst fluid samples (n = 23) from benign, borderline and malignant ovarian tumours in order to shed more light into ovarian tumour and cancer development. The analysis revealed that citrate was elevated in benign versus malignant tumours, while the amino acid lysine was elevated in malignant versus non-malignant tumours, both at a 5% significance level. Choline and lactate also had progressively increasing levels from benign to borderline to malignant samples. Finally, hypoxanthine was detected exclusively in a sub-cohort of the malignant tumours. This metabonomic study demonstrates that ovarian cyst fluid samples have potential to be used to distinguish between the different types of ovarian epithelial tumours. Furthermore, the respective metabolic profiles contain mechanistic information which could help identify biomarkers and therapeutic targets for ovarian tumours. PMID:26769844

  14. Metabonomic analysis of ovarian tumour cyst fluid by proton nuclear magnetic resonance spectroscopy

    PubMed Central

    Kyriakides, Michael; Rama, Nona; Sidhu, Jasmin; Gabra, Hani; Keun, Hector C.; El-Bahrawy, Mona

    2016-01-01

    The majority of ovarian tumours are of the epithelial type, which can be sub classified as benign, borderline or malignant. Epithelial tumours usually have cystic spaces filled with cyst fluid, the metabolic profile of which reflects the metabolic activity of the tumour cells, due to their close proximity. The approach of metabonomics using 1H-NMR spectroscopy was employed to characterize the metabolic profiles of ovarian cyst fluid samples (n = 23) from benign, borderline and malignant ovarian tumours in order to shed more light into ovarian tumour and cancer development. The analysis revealed that citrate was elevated in benign versus malignant tumours, while the amino acid lysine was elevated in malignant versus non-malignant tumours, both at a 5% significance level. Choline and lactate also had progressively increasing levels from benign to borderline to malignant samples. Finally, hypoxanthine was detected exclusively in a sub-cohort of the malignant tumours. This metabonomic study demonstrates that ovarian cyst fluid samples have potential to be used to distinguish between the different types of ovarian epithelial tumours. Furthermore, the respective metabolic profiles contain mechanistic information which could help identify biomarkers and therapeutic targets for ovarian tumours. PMID:26769844

  15. NK cells engineered to express a GD2-specific antigen receptor display built-in ADCC-like activity against tumour cells of neuroectodermal origin

    PubMed Central

    Esser, Ruth; Müller, Tina; Stefes, Dörthe; Kloess, Stephan; Seidel, Diana; Gillies, Stephen D; Aperlo-Iffland, Christel; Huston, James S; Uherek, Christoph; Schönfeld, Kurt; Tonn, Torsten; Huebener, Nicole; Lode, Holger N; Koehl, Ulrike; Wels, Winfried S

    2012-01-01

    Abstract Treatment of high-risk neuroblastoma (NB) represents a major challenge in paediatric oncology. Alternative therapeutic strategies include antibodies targeting the disialoganglioside GD2, which is expressed at high levels on NB cells, and infusion of donor-derived natural killer (NK) cells. To combine specific antibody-mediated recognition of NB cells with the potent cytotoxic activity of NK cells, here we generated clonal derivatives of the clinically applicable human NK cell line NK-92 that stably express a GD2-specific chimeric antigen receptor (CAR) comprising an anti-GD2 ch14.18 single chain Fv antibody fusion protein with CD3-ζ chain as a signalling moiety. CAR expression by gene-modified NK cells facilitated effective recognition and elimination of established GD2 expressing NB cells, which were resistant to parental NK-92. In the case of intrinsically NK-sensitive NB cell lines, we observed markedly increased cell killing activity of retargeted NK-92 cells. Enhanced cell killing was strictly dependent on specific recognition of the target antigen and could be blocked by GD2-specific antibody or anti-idiotypic antibody occupying the CAR’s cell recognition domain. Importantly, strongly enhanced cytotoxicity of the GD2-specific NK cells was also found against primary NB cells and GD2 expressing tumour cells of other origins, demonstrating the potential clinical utility of the retargeted effector cells. PMID:21595822

  16. Biophysical models of tumour growth

    NASA Astrophysics Data System (ADS)

    Tracqui, P.

    2009-05-01

    Tumour growth is a multifactorial process, which has stimulated in recent decades the development of numerous models trying to figure out the mechanisms controlling solid tumours morphogenesis. While the earliest models were focusing on cell proliferation kinetics, modulated by the availability of supplied nutrients, new modelling approaches emphasize the crucial role of several biophysical processes, including local matrix remodelling, active cell migration and traction, and reshaping of host tissue vasculature. After a brief presentation of this experimental background, this review will outline a number of representative models describing, at different scales, the growth of avascular and vascularized tumours. Special attention will be paid to the formulation of tumour-host tissue interactions that selectively drive changes in tumour size and morphology, and which are notably mediated by the mechanical status and elasticity of the tumour microenvironment. Emergence of invasive behaviour through growth instabilities at the tumour-host interface will be presented considering both reaction-diffusion and mechano-cellular models. In the latter part of the review, patient-oriented implications of tumour growth modelling are outlined in the context of brain tumours. Some conceptual views of the adaptive strategies and selective barriers that govern tumour evolution are presented in conclusion as potential guidelines for the development of future models.

  17. Toxicity Profiles In Vivo in Mice and Antitumour Activity in Tumour-Bearing Mice of Di- and Triorganotin Compounds

    PubMed Central

    Willem, R.; Dalil, H.; de Vos, D.; Kuiper, C. M.; Peters, G. J.

    1998-01-01

    The in vivo toxicity profiles in mice and the antitumour activity in tumour bearing mice were screened for four di-n-butyltin and five triorganotin carboxylates, di-n-butyltin diterebate (5), bis(phenylacetate) (6), bis(deoxycholate) (7), bis(lithocholate) (8), tri-n-butyltin terebate (9), cinnamate (10), and triphenyltin terebate (11). At their maximum tolerated dosis (MTD), no antitumour effect (T/C ~1) was observed for the compounds 5, 7, 9, 10 and 11. The compounds 6 (T/C = 0.51) and 8 (T/C = 0.42) showed clear antitumour activity after single dose administration and might therefore be of interest for further antitumour activity studies. PMID:18475827

  18. A systematic review of active treatment options in patients with desmoid tumours

    PubMed Central

    Yao, X.; Corbett, T.; Gupta, A.A.; Kandel, R.A.; Verma, S.; Werier, J.; Ghert, M.

    2014-01-01

    Introduction We conducted a systematic review to determine the optimal treatment options in patients with desmoid tumours who have declined observational management. Methods A search was conducted of the medline and embase databases (1990 to September 2012), the Cochrane Library, and relevant guideline Web sites and conference materials. Results One systematic review and forty-six studies met the preplanned study selection criteria; data from twenty-eight articles were extracted and analyzed. For local control, three studies reported a statistically significant difference in favour of surgery plus radiotherapy (rt) compared with surgery alone, and one study did not; two studies reported the lack of a statistical difference between surgery plus rt and rt alone in maintaining local control. Multivariate risk factors for local recurrence included positive surgical margins and young patient age. Single-agent imatinib led to a progression-free survival rate of 55% at 2 years and 58% at 3 years. Methotrexate plus vinblastine led to a progression-free survival rate of 67% at 10 years. Significant toxicities were reported for all treatment modalities, including surgical morbidity, and rt- and chemotherapy-related toxicities. Conclusions In patients who have declined observational management, the local control rate was higher with surgery plus rt than with surgery alone. However, the additional rt-related complications should be considered in treatment decision-making. Surgery, rt, and systemic therapy are all reasonable treatment options for patients with desmoid tumours. PMID:25089111

  19. Active debris removal of multiple priority targets

    NASA Astrophysics Data System (ADS)

    Braun, Vitali; Lüpken, A.; Flegel, S.; Gelhaus, J.; Möckel, M.; Kebschull, C.; Wiedemann, C.; Vörsmann, P.

    2013-05-01

    Today's space debris environment shows major concentrations of objects within distinct orbital regions for nearly all size regimes. The most critical region is found at orbital altitudes near 800 km with high declinations. Within this region many satellites are operated in so called sun-synchronous orbits (SSO). Among those, there are Earth observation, communication and weather satellites. Due to the orbital geometry in SSO, head-on encounters with relative velocities of about 15 km/s are most probable and would thus result in highly energetic collisions, which are often referred to as catastrophic collisions, leading to the complete fragmentation of the participating objects. So called feedback collisions can then be triggered by the newly generated fragments, thus leading to a further population increase in the affected orbital region. This effect is known as the Kessler syndrome.Current studies show that catastrophic collisions are not a major problem today, but will become the main process for debris generation within the SSO region in the near future, even without any further launches. In order to avoid this effect, objects with a major impact on collisional cascading have to be actively removed from the critical region after their end of life. Not having the capability to perform an end-of-life maneuver in order to transfer to a graveyard orbit or to de-orbit, many satellites and rocket bodies would have to be de-orbited within a dedicated mission. In such a mission, a service satellite would perform a de-orbit maneuver, after having docked to a specific target.In this paper, chemical and electric propulsion systems were analysed with the main focus on removing multiple targets within one single mission. The targets were chosen from a previously defined priority list in order to enhance the mission efficiency. Total mission time, ΔV and system mass were identified as key parameters to allow for an evaluation of the different concepts. It was shown that it

  20. miR-196b directly targets both HOXA9/MEIS1 oncogenes and FAS tumour suppressor in MLL-rearranged leukaemia

    PubMed Central

    Li, Zejuan; Huang, Hao; Chen, Ping; He, Miao; Li, Yuanyuan; Arnovitz, Stephen; Jiang, Xi; He, Chunjiang; Hyjek, Elizabeth; Zhang, Jun; Zhang, Zhiyu; Elkahloun, Abdel; Cao, Donglin; Shen, Chen; Wunderlich, Mark; Wang, Yungui; Neilly, Mary Beth; Jin, Jie; Wei, Minjie; Lu, Jun; Valk, Peter J.M.; Delwel, Ruud; Lowenberg, Bob; Le Beau, Michelle M.; Vardiman, James; Mulloy, James C.; Zeleznik-Le, Nancy J.; Liu, Paul P.; Zhang, Jiwang; Chen, Jianjun

    2012-01-01

    HOXA9, and MEIS1 have essential oncogenic roles in mixed lineage leukaemia (MLL)-rearranged leukaemia. Here we show that they are direct targets of miRNA-196b, a microRNA (miRNA) located adjacent to and co-expressed with HOXA9, in MLL-rearranged leukaemic cells. Forced expression of miR-196b significantly delays MLL-fusion-mediated leukemogenesis in primary bone marrow transplantation through suppressing Hoxa9/Meis1 expression. However, ectopic expression of miR-196b results in more aggressive leukaemic phenotypes and causes much faster leukemogenesis in secondary transplantation than MLL fusion alone, likely through the further repression of Fas expression, a proapoptotic gene downregulated in MLL-rearranged leukaemia. Overexpression of FAS significantly inhibits leukemogenesis and reverses miR-196b-mediated phenotypes. Targeting Hoxa9/Meis1 and Fas by miR-196b is probably also important for normal haematopoiesis. Thus, our results uncover a previously unappreciated miRNA-regulation mechanism by which a single miRNA may target both oncogenes and tumour suppressors, simultaneously, or, sequentially, in tumourigenesis and normal development per cell differentiation, indicating that miRNA regulation is much more complex than previously thought. PMID:22353710

  1. Bacterial-mediated DNA delivery to tumour associated phagocytic cells.

    PubMed

    Byrne, W L; Murphy, C T; Cronin, M; Wirth, T; Tangney, M

    2014-12-28

    Phagocytic cells including macrophages, dendritic cells and neutrophils are now recognised as playing a negative role in many disease settings including cancer. In particular, macrophages are known to play a pathophysiological role in multiple diseases and present a valid and ubiquitous therapeutic target. The technology to target these phagocytic cells in situ, both selectively and efficiently, is required in order to translate novel therapeutic modalities into clinical reality. We present a novel delivery strategy using non-pathogenic bacteria to effect gene delivery specifically to tumour-associated phagocytic cells. Non-invasive bacteria lack the ability to actively enter host cells, except for phagocytic cells. We exploit this natural property to effect 'passive transfection' of tumour-associated phagocytic cells following direct administration of transgene-loaded bacteria to tumour regions. Using an in vitro-differentiated human monocyte cell line and two in vivo mouse models (an ovarian cancer ascites and a solid colon tumour model) proof of delivery is demonstrated with bacteria carrying reporter constructs. The results confirm that the delivery strategy is specific for phagocytic cells and that the bacterial vector itself recruits more phagocytic cells to the tumour. While proof of delivery to phagocytic cells is demonstrated in vivo for solid and ascites tumour models, this strategy may be applied to other settings, including non-cancer related disease. PMID:25466954

  2. Restraining FOXO3-dependent transcriptional BMF activation underpins tumour growth and metastasis of E-cadherin-negative breast cancer.

    PubMed

    Hornsveld, M; Tenhagen, M; van de Ven, R A; Smits, A M M; van Triest, M H; van Amersfoort, M; Kloet, D E A; Dansen, T B; Burgering, B M; Derksen, P W B

    2016-09-01

    Loss of cellular adhesion leads to the progression of breast cancer through acquisition of anchorage independence, also known as resistance to anoikis. Although inactivation of E-cadherin is essential for acquisition of anoikis resistance, it has remained unclear how metastatic breast cancer cells counterbalance the induction of apoptosis without E-cadherin-dependent cellular adhesion. We report here that E-cadherin inactivation in breast cancer cells induces PI3K/AKT-dependent FOXO3 inhibition and identify FOXO3 as a novel and direct transcriptional activator of the pro-apoptotic protein BMF. As a result, E-cadherin-negative breast fail to upregulate BMF upon transfer to anchorage independence, leading to anoikis resistance. Conversely, expression of BMF in E-cadherin-negative metastatic breast cancer cells is sufficient to inhibit tumour growth and dissemination in mice. In conclusion, we have identified repression of BMF as a major cue that underpins anoikis resistance and tumour dissemination in E-cadherin-deficient metastatic breast cancer. PMID:27035620

  3. Active Debris Removal of Multiple Priority Targets

    NASA Astrophysics Data System (ADS)

    Braun, Vitali; Flegel, Sven Kevin; Vörsmann, Peter; Wiedemann, Carsten; Gelhaus, Johannes; Moeckel, Marek; Kebschull, Christopher

    2012-07-01

    Today's space debris environment shows major concentrations of objects within distinct orbital regions for nearly all size regimes. The most critical region is found at orbital altitudes near 800 kilometers with high declinations. Within this region many satellites are operated in so called sun-synchronous orbits (SSO). Among those, there are Earth observation, communication and weather satellites. Due to the orbital geometry, head-on encounters with relative velocities of about 15 km/s are most probable and would thus result in highly energetic collisions, which are often referred to as catastrophic collisions, leading to the complete fragmentation of the participating objects. So called feedback collisions can then be triggered by the newly generated fragments, thus leading to a further population increase in the affected orbital region. This effect is known as the Kessler syndrome. Current studies show that catastrophic collisions are not a major problem today, but will become the main process for debris generation within the SSO region in the near future, even without any future launches. In order to avoid this effect, objects with a major impact on collisional cascading have to be actively removed from the critical region after their end of life. Not having the capability to perform an end-of-life maneuver in order to transfer to a graveyard orbit or to de-orbit, many satellites and rocket bodies would have to be de-orbited within a dedicated mission. In such a mission, a service satellite would perform a de-orbit maneuver, after having docked to a specific target. In this paper several systems, e.g. chemical and electrical engines are analysed with the main focus on removing multiple targets within one single mission. The service satellite has to undock from the previously de-orbited target in order to start the rendezvous and docking phase for a subsequent target. The targets are chosen from a previously defined priority list in order to enhance the mission

  4. Serial Next Generation Sequencing of Circulating Cell Free DNA Evaluating Tumour Clone Response To Molecularly Targeted Drug Administration

    PubMed Central

    Frenel, Jean Sebastien; Carreira, Suzanne; Goodall, Jane; Roda, Desam; Perez-Lopez, Raquel; Tunariu, Nina; Riisnaes, Ruth; Miranda, Susana; Figueiredo, Ines; NavaRodrigues, Daniel; Smith, Alan; Leux, Christophe; Garcia-Murillas, Isaac; Ferraldeschi, Roberta; Lorente, David; Mateo, Joaquin; Ong, Michael; Yap, Timothy A; Banerji, Udai; Tandefelt, Delila Gasi; Turner, Nick; Attard, Gerhardt; de Bono, Johann S

    2015-01-01

    Background We evaluated whether next generation sequencing (NGS) of cfDNA could be used for patient selection and as a tumor clone response biomarker in patients with advanced cancers participating in early phase clinical trials of targeted drugs. Methods Plasma samples from patients with known tumor mutations who completed at least 2 courses of investigational targeted therapy were collected monthly, until disease progression. NGS was performed sequentially on the Ion Torrent PGM platform. Results cfDNA was extracted from 39 patients with various tumor types. Treatments administered targeted mailnly the PI3K-AKT-mTOR pathway (n=28) or MEK (n=7). Overall 159 plasma samples were sequenced with a mean sequencing coverage achieved of 1,685X across experiments. At trial initiation (C1D1), 23 of 39 (59%) patients had at least one mutation identified in cfDNA (mean 2, range 1-5). TP53, PIK3CA and KRAS were the top 3 mutated genes identified, with 16 (39%), 9 (22%) and 8 (17%) different mutations, respectively. Out of these 23 patients, 13 received a targeted drug matching their tumor profile. For the 23 patients with cfDNA mutation at C1D1, the monitoring of mutation allele frequency (AF) in consecutive plasma samples during treatment with targeted drugs demonstrated potential treatment associated clonal responses. Longitudinal monitoring of cfDNA samples with multiple mutations indicated the presence of separate clones behaving discordantly. Molecular changes at cfDNA mutation level were associated with time to disease progression by RECIST criteria. Conclusion Targeted NGS of cfDNA has potential clinical utility to monitor the delivery of targeted therapies. PMID:26085511

  5. Targeted Next Generation Sequencing as a Reliable Diagnostic Assay for the Detection of Somatic Mutations in Tumours Using Minimal DNA Amounts from Formalin Fixed Paraffin Embedded Material

    PubMed Central

    Koudijs, Marco J.; Nijman, Ies; Hinrichs, John W. J.; Cuppen, Edwin; van Lieshout, Stef; Loberg, Robert D.; de Jonge, Maja; Voest, Emile E.; de Weger, Roel A.; Steeghs, Neeltje; Langenberg, Marlies H. G.; Sleijfer, Stefan; Willems, Stefan M.; Lolkema, Martijn P.

    2016-01-01

    Background Targeted Next Generation Sequencing (NGS) offers a way to implement testing of multiple genetic aberrations in diagnostic pathology practice, which is necessary for personalized cancer treatment. However, no standards regarding input material have been defined. This study therefore aimed to determine the effect of the type of input material (e.g. formalin fixed paraffin embedded (FFPE) versus fresh frozen (FF) tissue) on NGS derived results. Moreover, this study aimed to explore a standardized analysis pipeline to support consistent clinical decision-making. Method We used the Ion Torrent PGM sequencing platform in combination with the Ion AmpliSeq Cancer Hotspot Panel v2 to sequence frequently mutated regions in 50 cancer related genes, and validated the NGS detected variants in 250 FFPE samples using standard diagnostic assays. Next, 386 tumour samples were sequenced to explore the effect of input material on variant detection variables. For variant calling, Ion Torrent analysis software was supplemented with additional variant annotation and filtering. Results Both FFPE and FF tissue could be sequenced reliably with a sensitivity of 99.1%. Validation showed a 98.5% concordance between NGS and conventional sequencing techniques, where NGS provided both the advantage of low input DNA concentration and the detection of low-frequency variants. The reliability of mutation analysis could be further improved with manual inspection of sequence data. Conclusion Targeted NGS can be reliably implemented in cancer diagnostics using both FFPE and FF tissue when using appropriate analysis settings, even with low input DNA. PMID:26919633

  6. Enhanced immune recognition of cryptic glycan markers in human tumours

    PubMed Central

    Newsom-Davis, Thomas E; Wang, Denong; Steinman, Lawrence; Chen, Paul F-T; Wang, Lai-Xi; Simon, A Katharina; Screaton, Gavin R

    2009-01-01

    Abnormal glycosylation is one of the hallmarks of the cancer cell and is associated with tumour invasion and metastasis. The development of tumour associated carbohydrate antigen (TACA) vaccines has been problematic due to poor immunogenicity. However when appropriate targets can be identified, passive immunisation with monoclonal antibodies (mAbs) directed against TACAs have been shown to have anti-tumour activity. Fas ligand (FasL) is a transmembrane protein which induces apoptosis in cells expressing its receptor, Fas. When grafted into mice, FasL-expressing tumour cells break immunological tolerance to self-antigens and induce antibody mediated tumour immunity. Here, five IgM mAbs were produced from mice vaccinated with FasL-expressing B16F10 mouse melanoma cells. They recognise various syngeneic and allogeneic murine tumour cell lines. One mAb, TM10, recognises a range of human tumour cell lines including melanoma, prostate and ovarian cancer. It does not bind to untransformed cells. The epitopes recognised by all the mAbs were carbohydrates expressed on proteins. Using carbohydrate microarrays, the antigenic targets of TM10 were found to be high-mannose core structures of N-linked glycans. In normal cells high mannose clusters are hidden by extensive saccharide branching but they become exposed in cancer cells as a result of abnormal glycosylation pathways. Vaccination with FasL-expressing tumours therefore enables the immune system to break tolerance to self-antigens, allowing identification of novel TACAs that can form the basis of future humoral anti-cancer therapy. PMID:19223535

  7. Importance of P450 reductase activity in determining sensitivity of breast tumour cells to the bioreductive drug, tirapazamine (SR 4233).

    PubMed Central

    Patterson, A. V.; Barham, H. M.; Chinje, E. C.; Adams, G. E.; Harris, A. L.; Stratford, I. J.

    1995-01-01

    P450 reductase (NADPH:cytochrome P450 reductase, EC 1.6.2.4) is known to be important in the reductive activation of the benzotriazene-di-N-oxide tirapazamine (SR 4233). Using a panel of six human breast adenocarcinoma cell lines we have examined the relationship between P450 reductase activity and sensitivity to tirapazamine. The toxicity of tirapazamine was found to correlate strongly with P450 reductase activity following an acute (3 h) exposure under hypoxic conditions, the drug being most toxic in the cell lines with the highest P450 reductase activity. A similar correlation was also observed following a chronic (96 h) exposure to the drug in air but not following acute (3 h) exposure in air. We have also determined the ability of lysates prepared from the cell lines to metabolise tirapazamine to its two-electron reduced product, SR 4317, under hypoxic conditions using NADPH as an electron donor. The rate of SR 4317 formation was found to correlate both with P450 reductase activity and with sensitivity to tirapazamine, the highest rates of SR 4317 formation being associated with the highest levels of P450 reductase activity and the greatest sensitivity to the drug. These findings indicate a major role for P450 reductase in determining the hypoxic toxicity of tirapazamine in breast tumour cell lines. Images Figure 4 PMID:7577460

  8. Mitochondria-targeted antioxidants do not prevent tumour necrosis factor-induced necrosis of L929 cells.

    PubMed

    Jarvis, Reagan M; Göttert, Jana; Murphy, Michael P; Ledgerwood, Elizabeth C

    2007-09-01

    Mitochondrial production of reactive oxygen species (ROS) is widely reported as a central effector during TNF-induced necrosis. The effect of a family of mitochondria-targeted antioxidants on TNF-induced necrosis of L929 cells was studied. While the commonly used lipid-soluble antioxidant BHA effectively protected cells from TNF-induced necrosis, the mitochondria-targeted antioxidants MitoQ(3), MitoQ(5), MitoQ(10) and MitoPBN had no effect on TNF-induced necrosis. Since BHA also acts as an uncoupler of mitochondrial membrane potential, two additional uncouplers were tested. FCCP and CCCP both provided dose-dependent inhibition of TNF-induced necrosis. In conclusion, the generation of mitochondrial ROS may not be necessary for TNF-induced necrosis. Instead, these results suggest alternative mitochondrial functions, such as a respiration-dependent process, are critical for necrotic death. PMID:17729122

  9. Molecular mechanisms for tumour resistance to chemotherapy.

    PubMed

    Pan, Shu-Ting; Li, Zhi-Ling; He, Zhi-Xu; Qiu, Jia-Xuan; Zhou, Shu-Feng

    2016-08-01

    Chemotherapy is one of the prevailing methods used to treat malignant tumours, but the outcome and prognosis of tumour patients are not optimistic. Cancer cells gradually generate resistance to almost all chemotherapeutic drugs via a variety of distinct mechanisms and pathways. Chemotherapeutic resistance, either intrinsic or acquired, is caused and sustained by reduced drug accumulation and increased drug export, alterations in drug targets and signalling transduction molecules, increased repair of drug-induced DNA damage, and evasion of apoptosis. In order to better understand the mechanisms of chemoresistance, this review highlights our current knowledge of the role of altered drug metabolism and transport and deregulation of apoptosis and autophagy in the development of tumour chemoresistance. Reduced intracellular activation of prodrugs (e.g. thiotepa and tegafur) or enhanced drug inactivation by Phase I and II enzymes contributes to the development of chemoresistance. Both primary and acquired resistance can be caused by alterations in the transport of anticancer drugs which is mediated by a variety of drug transporters such as P-glycoprotein (P-gp), multidrug resistance associated proteins, and breast cancer resistance protein. Presently there is a line of evidence indicating that deregulation of programmed cell death including apoptosis and autophagy is also an important mechanism for tumour resistance to anticancer drugs. Reversal of chemoresistance is likely via pharmacological and biological approaches. Further studies are warranted to grasp the full picture of how each type of cancer cells develop resistance to anticancer drugs and to identify novel strategies to overcome it. PMID:27097837

  10. MEK inhibition prevents tumour-shed transforming growth factor-β-induced T-regulatory cell augmentation in tumour milieu.

    PubMed

    Hossain, Dewan M S; Panda, Abir K; Chakrabarty, Sreeparna; Bhattacharjee, Pushpak; Kajal, Kirti; Mohanty, Suchismita; Sarkar, Irene; Sarkar, Diptendra K; Kar, Santosh K; Sa, Gaurisankar

    2015-04-01

    Tumour progression is associated with immune-suppressive conditions that facilitate the escape of tumour cells from the regimen of immune cells, subsequently paralysing the host defence mechanisms. Induction of CD4(+)  CD25(+)  FoxP3(+) T regulatory (Treg) cells has been implicated in the tumour immune escape mechanism, although the novel anti-cancer treatment strategies targeting Treg cells remain unknown. The focus of this study is to define the interaction between tumour and immune system, i.e. how immune tolerance starts and gradually leads to the induction of adaptive Treg cells in the tumour microenvironment. Our study identified hyperactivated mitogen-activated protein kinase kinase (MEK)/extracellular signal-regulated kinase (ERK) -signalling as a potential target for reversing Treg cell augmentation in breast cancer patients. In more mechanistic detail, pharmacological inhibitors of MEK/ERK signalling inhibited transforming growth factor-β (TGF-β) production in tumour cells that essentially blocked TGF-β-SMAD3/SMAD4-mediated induction of CD25/interleukin-2 receptor α on CD4(+) T-cell surface. As a result high-affinity binding of interleukin-2 on those cells was prohibited, causing lack of Janus kinase 1 (JAK1)/JAK3-mediated signal transducer and activator of transcription 3 (STAT3)/STAT5 activation required for FoxP3 expression. Finally, for a more radical approach towards a safe MEK inhibitor, we validate the potential of multi-kinase inhibitor curcumin, especially the nano-curcumin made out of pure curcumin with greater bioavailability; in repealing tumour-shed TGF-β-induced Treg cell augmentation. PMID:25284464

  11. The suppression of fibroblast growth factor 2/fibroblast growth factor 4-dependent tumour angiogenesis and growth by the anti-growth factor activity of dextran derivative (CMDB7).

    PubMed Central

    Bagheri-Yarmand, R.; Kourbali, Y.; Mabilat, C.; Morère, J. F.; Martin, A.; Lu, H.; Soria, C.; Jozefonvicz, J.; Crépin, M.

    1998-01-01

    Our previous studies showed that carboxymethyl benzylamide dextran (CMDB7) blocks basic fibroblast growth factor (FGF-2)-dependent cell proliferation of a human breast epithelial line (HBL100), suggesting its potential role as a potent antiangiogenic substance. The derived cell line (HH9), which was transformed with the hst/FGF4 gene, has been shown to be highly proliferative in vitro and to induce angiogenic tumours in nude mice. We show here that CMDB7 inhibits the mitogenic activities of the conditioned media from HBL 100 and HH9 cells in a dose-dependent manner. When HH9 cells were injected s.c. into nude mice, CMDB7 treatment (300 mg kg(-1) week(-1)) suppressed the tumour take and the tumour growth by about 50% and 80% respectively. Immunohistochemical analysis showed a highly significant decrease, by more than threefold, in the endothelial density of viable tumour regions, together with a significant increase in the necrosis area. This antiangiogenic activity of CMDB7 was further demonstrated by direct inhibition of calf pulmonary artery (CPAE) and human umbilical vein (HUVEC) endothelial cell proliferation and migration in vitro. In addition, we showed that CMDB7 inhibits specifically the mitogenic effects of the growth factors that bind to heparin such as FGF-2, FGF-4, platelet-derived growth factor (PDGF-BB) and transforming growth factor (TGF-beta1), but not those of epidermal growth factor (EGF) and insulin-like growth factor (IGF-1). These results demonstrate that CMDB7 inhibits FGF-2/FGF-4-dependent tumour growth and angiogenesis, most likely by disrupting the autocrine and paracrine effects of growth factors released from the tumour cells. Images Figure 4 PMID:9662260

  12. Promotion of tumour proliferation, migration and invasion by miR-92b in targeting RECK in osteosarcoma.

    PubMed

    Zhou, Zhenhua; Wang, Zhiwei; Wei, Haifeng; Wu, Sujia; Wang, Xudong; Xiao, Jianru

    2016-06-01

    MicroRNAs play important roles in the development of cancers. Although miR-92b has been reported to promote the tumorigenesis of some cancers, its role in osteosarcoma remains unknown. In the present study, we focused on the expression, function and mechanisms of miR-92b in osteosarcoma development. The miRNA miR-92b was up-regulated in osteosarcoma cell lines and tissues; miR-92b up-regulation correlated with poor prognosis in osteosarcoma. Overexpression of miR-92b promoted osteosarcoma cell proliferation, migration and invasion, which was abrogated by miR-92b inhibition. Reversion-inducing, cysteine-rich protein with kazal motifs (RECK) was identified as the direct and functional target of miR-92b in osteosarcoma. Importantly, restoring RECK expression abrogated increases in cell growth, motility and invasiveness induced by miR-92b RECK was down-regulated in osteosarcoma tissues, and its expression level negatively correlated with miR-92b Collectively, our results indicate that miR-92b acts as an oncogenic miRNA and may be a therapeutic target in osteosarcoma. PMID:26993249

  13. Growth arrest vs direct cytotoxicity and the importance of molecular structure for the in vitro anti-tumour activity of ether lipids.

    PubMed Central

    Lohmeyer, M.; Workman, P.

    1995-01-01

    A panel of 25 different lipid agents was evaluated for in vitro activity against HT29 human colon carcinoma and HL60 promyelocytic leukaemia cells by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The structure-activity relationships seen with this series, including those for four sets of positional or stereoisomers, indicate that specific receptor proteins are unlikely as targets for anti-tumour lipid (ATL) action. Additional data confirm the lack of involvement of the platelet-activating factor receptor in particular and suggest that metabolic stability is a most important determinant of ATL activity. More detailed studies, with 1-O-octadecyl-2-O-methyl-rac-glycero-3-phosphocholine (ET18-OCH3) and (+/-)-2-(Hydroxy[tetrahydro-2-(octadecyloxy)methylfuran-2- yl]methoxyphosphinyloxy)-N,N,N,-trimethylethaniminium hydroxide (SRI 62-834), suggest three different modes of activity, depending on drug concentration and exposure time. Low doses of up to 5 microM in standard serum-containing medium cause population growth arrest after prolonged exposure. Growth arrest was associated with a leaky G2/M block as determined by flow cytometry. These effects are reversible. Intermediate concentrations (5-40 microM) were cytotoxic, causing a net reduction in cell numbers after 2-3 days. At even higher concentrations, all lipids caused rapid, direct membrane lysis. When the clonogenic assay was used to assess the effects of ATLs, most agents reduced colony formation at concentrations above 5 microM. However, some compounds proved stimulatory at nanomolar concentrations, suggesting that they might possess mitogenic properties. These results, particularly those concerning the concentration and time dependence, may be relevant to current clinical trials with ether lipids. PMID:7640206

  14. Mutational analysis of PI3K/AKT and RAS/RAF pathway activation in malignant salivary gland tumours with a new mutation of PIK3CA.

    PubMed

    Shalmon, B; Drendel, M; Wolf, M; Hirshberg, A; Cohen, Y

    2016-06-01

    The phosphoinositide 3-kinase (PIK3)/v-akt murine thymoma (AKT) oncogene pathway and the RAS/RAF pathway are involved in regulating the signalling of multiple biological processes, including apoptosis, metabolism, cell proliferation, and cell growth. Mutations in the genes within these pathways are frequently found in several tumours. The aim of this study was to investigate the frequency of mutations in the PIK3CA, BRAF, and KRAS genes in cases of malignant salivary gland tumours. Mutational analysis of the PIK3CA, KRAS, and BRAF genes was performed by direct sequencing of material from 21 patients with malignant salivary gland tumours who underwent surgery between 1992 and 2001. No mutations were found in the KRAS exon 2, BRAF exon 15, or PIK3CA exon 9 genes. However, an unpublished mutation of the PIK3CA gene in exon 20 (W1051 stop mutation) was found in one case of adenocarcinoma NOS. The impact of this mutation on the biological behaviour of the tumour has yet to be explored, however the patient with adenocarcinoma NOS harbouring this mutation has survived for over 20 years following surgery despite a high stage at presentation. Further studies with more homogeneous patient cohorts are needed to address whether this mutation reflects a different clinical presentation and may benefit from targeted treatment strategies. PMID:26811072

  15. Identification of genes involved in the biology of atypical teratoid/rhabdoid tumours using Drosophila melanogaster

    NASA Astrophysics Data System (ADS)

    Jeibmann, Astrid; Eikmeier, Kristin; Linge, Anna; Kool, Marcel; Koos, Björn; Schulz, Jacqueline; Albrecht, Stefanie; Bartelheim, Kerstin; Frühwald, Michael C.; Pfister, Stefan M.; Paulus, Werner; Hasselblatt, Martin

    2014-06-01

    Atypical teratoid/rhabdoid tumours (AT/RT) are malignant brain tumours. Unlike most other human brain tumours, AT/RT are characterized by inactivation of one single gene, SMARCB1. SMARCB1 is a member of the evolutionarily conserved SWI/SNF chromatin remodelling complex, which has an important role in the control of cell differentiation and proliferation. Little is known, however, about the pathways involved in the oncogenic effects of SMARCB1 inactivation, which might also represent targets for treatment. Here we report a comprehensive genetic screen in the fruit fly that revealed several genes not yet associated with loss of snr1, the Drosophila homologue of SMARCB1. We confirm the functional role of identified genes (including merlin, kibra and expanded, known to regulate hippo signalling pathway activity) in human rhabdoid tumour cell lines and AT/RT tumour samples. These results demonstrate that fly models can be employed for the identification of clinically relevant pathways in human cancer.

  16. Tumour-initiating cells vs. cancer 'stem' cells and CD133: What's in the name?

    SciTech Connect

    Neuzil, Jiri; E-mail: j.neuzil@griffith.edu.au; Stantic, Marina; Zobalova, Renata; Chladova, Jaromira; Wang, Xiufang; Prochazka, Lubomir; Dong, Lanfeng; Andera, Ladislav; Ralph, Stephen J.

    2007-04-20

    Recent evidence suggests that a subset of cells within a tumour have 'stem-like' characteristics. These tumour-initiating cells, distinct from non-malignant stem cells, show low proliferative rates, high self-renewing capacity, propensity to differentiate into actively proliferating tumour cells, resistance to chemotherapy or radiation, and they are often characterised by elevated expression of the stem cell surface marker CD133. Understanding the molecular biology of the CD133{sup +} cancer cells is now essential for developing more effective cancer treatments. These may include drugs targeting organelles, such as mitochondria or lysosomes, using highly efficient and selective inducers of apoptosis. Alternatively, agents or treatment regimens that enhance sensitivity of these therapy-resistant 'tumour stem cells' to the current or emerging anti-tumour drugs would be of interest as well.

  17. Functional and Biological Role of Endothelial Precursor Cells in Tumour Progression: A New Potential Therapeutic Target in Haematological Malignancies.

    PubMed

    Reale, Antonia; Melaccio, Assunta; Lamanuzzi, Aurelia; Saltarella, Ilaria; Dammacco, Franco; Vacca, Angelo; Ria, Roberto

    2016-01-01

    It was believed that vasculogenesis occurred only during embryo life and that postnatal formation of vessels arose from angiogenesis. Recent findings demonstrate the existence of Endothelial Precursor Cells (EPCs), which take partin postnatal vasculogenesis. EPCs are recruited from the bone marrow under the stimulation of growth factors and cytokines and reach the sites of neovascularization in both physiological and pathological conditions such as malignancies where they contribute to the "angiogenic switch" and tumor progression. An implementation of circulating EPCs in the bloodstream of patients with haematological malignancies has been demonstrated. This increase is strictly related to the bone marrow microvessel density and correlated with a poor prognosis. The EPCs characterization is a very complex process and still under investigation. This literature review aims to provide an overview of the functional and biological role of EPCs in haematological malignancies and to investigate their potential as a new cancer therapeutic target. PMID:26788072

  18. Characterization of the human activator protein-2gamma (AP-2gamma) gene: control of expression by Sp1/Sp3 in breast tumour cells.

    PubMed Central

    Hasleton, Mark D; Ibbitt, J Claire; Hurst, Helen C

    2003-01-01

    The activator protein-2 (AP-2) family of DNA-binding transcription factors are developmentally regulated and also play a role in human neoplasia. In particular, the AP-2gamma protein has been shown to be overexpressed in a high percentage of breast tumours. In the present study, we report the complete sequence determination of the human TFAP2C gene encoding the AP-2gamma transcription factor plus the mapping of the transcription start site used in breast tumour-derived cells. The 5'-end of the gene lies within a CpG island and transcription is initiated at a single site within a classical initiator motif. We have gone on to investigate why some breast tumour-derived cell lines readily express AP-2gamma, whereas others do not, and show that the proximal promoter (+191 to -312) is differentially active in the two cell phenotypes. DNase footprinting led to the identification of three Sp1/Sp3-binding sites within this region, two of which are absolutely required both for promoter function and cell-type-specific activity. By Western blotting a panel of expressing and non-expressing breast tumour lines we show that the latter have higher levels of Sp3. Furthermore, increasing Sp3 levels in AP-2gamma-expressing cells led to the repression of AP-2gamma promoter activity, particularly when Sp3 inhibitory function was maximized through sumoylation. We propose that differences in the level and activity of Sp3 between breast tumour lines can determine the expression level of their AP-2gamma gene. PMID:12733991

  19. [Drug therapy for neuroendocrine tumours].

    PubMed

    Tóth, Miklós

    2013-09-29

    The author aims to review the established medical treatment options of neuroendocrine tumours, which have expanded greatly in recent years and present the most important aspects to be considered in planning patients' management. Medical treatment is usually considered in advanced stages of these tumours, as well as in cases of hormone overproduction. Somatostatin analogues have been known to be effective in alleviating hormone excess syndromes, especially carcinoid syndrome for the past 25 years. There is a convincing evidence that the somatostatin analogue octreotide is useful as an antitumor agent, at least in well-differentiated small intestinal neuroendocrine tumours and probably also in those of pancreatic origin. Interferons may be also used and the indications for their use may be almost the same. Optimal patient selection is mandatory for the use of cytotoxic chemotherapy. Streptozotocin- and, recently, temozolomide-based chemotherapies should be considered in progressive phases of well differentiated (G1/G2) pancreatic neuroendocrine tumours. A cisplatin-etoposide combination is the first choice for the treatment of G3 neuroendocrine carcinomas of any origin. Recently, the mammalian target of rapamycin inhibitor everolimus and the combined tyrosine kinase inhibitor sunitinib were registered for the treatment of G1/G2 pancreatic neuroendocrine tumours. The most recent drug treatment recommendations and therapeutic algorithms to improve systemic therapy in patients with neuroendocrine tumours are summarized and novel drug candidates with particular potential for future management of these tumours are outlined. PMID:24058101

  20. Synthesis and evaluation of condensed magnetic nanocrystal clusters with in vivo multispectral optoacoustic tomography for tumour targeting.

    PubMed

    Sarigiannis, Yiannis; Kolokithas-Ntoukas, Αrgiris; Beziere, Nicolas; Zbořil, Radek; Papadimitriou, Evangelia; Avgoustakis, Konstantinos; Lamprou, Margarita; Medrikova, Zdenka; Rousalis, Elias; Ntziachristos, Vasilis; Bakandritsos, Aristides

    2016-06-01

    Colloidal clusters of magnetic iron oxide nanocrystals (MIONs), particularly in the condensed pattern (co-CNCs), have emerged as new superstructures to improve further the performance of MIONs in applications pertaining to magnetic manipulation (drug delivery) and magnetic resonance imaging (MRI). Exploitation of the advantages they represent and their establishment in the area of nanomedicine demands a particular set of assets. The present work describes the development and evaluation of MION-based co-CNCs featuring for the first time such assets: High magnetization, as well as magnetic content and moment, high relaxivities (r2 = 400 and [Formula: see text] ) and intrinsic loss power (2.3 nH m(2) kgFe(-1)) are combined with unprecedented colloidal stability and structural integrity, stealth and drug-loading properties. The reported nanoconstructs are endowed with additional important features such as cost-effective synthesis and storage, prolonged self-life and biocompatibility. It is finally showcased with in vivo multispectral optoacoustic tomography how these properties culminate in a system suitable for targeting breast cancer and for forceful in vivo manipulation with low magnetic field gradients. PMID:27045357

  1. How targets select activation or repression in response to Wnt.

    PubMed

    Murgan, Sabrina; Bertrand, Vincent

    2015-01-01

    In metazoans, the Wnt signaling pathway plays a key role in the regulation of binary decisions during development. During this process different sets of target genes are activated in cells where the Wnt pathway is active (classic target genes) versus cells where the pathway is inactive (opposite target genes). While the mechanism of transcriptional activation is well understood for classic target genes, how opposite target genes are activated in the absence of Wnt remains poorly characterized. Here we discuss how the key transcriptional mediator of the Wnt pathway, the TCF family member POP-1, regulates opposite target genes during C. elegans development. We examine recent findings suggesting that the direction of the transcriptional output (activation or repression) can be determined by the way TCF is recruited and physically interacts with its target gene. PMID:27123368

  2. Tumour exosomes display differential mechanical and complement activation properties dependent on malignant state: implications in endothelial leakiness

    PubMed Central

    Whitehead, Bradley; Wu, LinPing; Hvam, Michael Lykke; Aslan, Husnu; Dong, Mingdong; Dyrskjøt, Lars; Ostenfeld, Marie Stampe; Moghimi, Seyed Moein; Howard, Kenneth Alan

    2015-01-01

    Background Exosomes have been implicated in tumour progression and metastatic spread. Little is known of the effect of mechanical and innate immune interactions of malignant cell-derived exosomes on endothelial integrity, which may relate to increased extravasation of circulating tumour cells and, therefore, increased metastatic spread. Methods Exosomes isolated from non-malignant immortalized HCV-29 and isogenic malignant non-metastatic T24 and malignant metastatic FL3 bladder cells were characterized by nanoparticle tracking analysis and quantitative nanomechanical mapping atomic force microscopy (QNM AFM) to determine size and nanomechanical properties. Effect of HCV-29, T24 and FL3 exosomes on human umbilical vein endothelial cell (HUVEC) monolayer integrity was determined by transendothelial electrical resistance (TEER) measurements and transport was determined by flow cytometry. Complement activation studies in human serum of malignant and non-malignant cell-derived exosomes were performed. Results FL3, T24 and HCV-29 cells produced exosomes at similar concentration per cell (6.64, 6.61 and 6.46×104 exosomes per cell for FL3, T24 and HCV-29 cells, respectively) and of similar size (120.2 nm for FL3, 127.6 nm for T24 and 117.9 nm for HCV-29, respectively). T24 and FL3 cell-derived exosomes exhibited a markedly reduced stiffness, 95 MPa and 280 MPa, respectively, compared with 1,527 MPa with non-malignant HCV-29 cell-derived exosomes determined by QNM AFM. FL3 and T24 exosomes induced endothelial disruption as measured by a decrease in TEER in HUVEC monolayers, whereas no effect was observed for HCV-29 derived exosomes. FL3 and T24 exosomes traffic more readily (11.6 and 21.4% of applied exosomes, respectively) across HUVEC monolayers than HCV-29 derived exosomes (7.2% of applied exosomes). Malignant cell-derived exosomes activated complement through calcium-sensitive pathways in a concentration-dependent manner. Conclusions Malignant (metastatic and non

  3. An active target concept for the electronuclear reactor

    SciTech Connect

    Grebyonkin, K.F.; Shzerebzov, A.L.; Kandiev, Ya.Z.; Maloyaroslavtsev, A.N.; Modin, V.N.; Orlov, A.I.; Peschkov, I.A.; Scherbakov, A.P.

    1995-12-31

    Preliminary identification of the components and efficiency estimations for the proposed (by Chelyabinsk-70) concept of active target for electronuclear reactor are goals of this work. (The electronuclear reactor comprises a high-energy proton acclerator, a high-atomic-number target (lead, tungsten) which produces neutrons from the protons, and a subcritical blanket.) Results of preliminary neutron and thermal-hydraulic simulations of the target are represented in the paper and preliminary detailing of the active target components is performed. It is shown that the use of active target can lead to an essential reduction of the requirements to the accelerator power without deterioration of the safety of the system.

  4. Anti-tumour effect of metformin in canine mammary gland tumour cells.

    PubMed

    Saeki, K; Watanabe, M; Tsuboi, M; Sugano, S; Yoshitake, R; Tanaka, Y; Ong, S M; Saito, T; Matsumoto, K; Fujita, N; Nishimura, R; Nakagawa, T

    2015-08-01

    Metformin is an oral hypoglycaemic drug used in type 2 diabetes. Its pharmacological activity reportedly involves mitochondrial respiratory complex I, and mitochondrial respiratory complex inhibitors have a strong inhibitory effect on the growth of metastatic canine mammary gland tumour (CMGT) cell lines. It is hypothesised that metformin has selective anti-tumour effects on metastatic CMGT cells. The aim of this study was to investigate the in vitro effect of metformin on cell growth, production of ATP and reactive oxygen species (ROS), and the AMP-activated protein kinase (AMPK) mammalian target of rapamycin (mTOR) pathway in two CMGT clonal cell lines with different metastatic potential. In addition, transcriptome analysis was used to determine cellular processes disrupted by metformin and in vivo anti-tumour effects were examined in a mouse xenograft model. Metformin inhibited CMGT cell growth in vitro, with the metastatic clone (CHMp-5b) displaying greater sensitivity. ATP depletion and ROS elevation were observed to a similar extent in the metastatic and non-metastatic (CHMp-13a) cell lines after metformin exposure. However, subsequent AMPK activation and mTOR pathway inhibition were prominent only in metformin-insensitive non-metastatic cells. Microarray analysis revealed inhibition of cell cycle progression by metformin treatment in CHMp-5b cells, which was further confirmed by Western blotting and cell cycle analysis. Additionally, metformin significantly suppressed tumour growth in xenografted metastatic CMGT cells. In conclusion, metformin exhibited an anti-tumour effect in metastatic CMGT cells through AMPK-independent cell cycle arrest. Its mechanism of action differed in the non-metastatic clone, where AMPK activation and mTOR inhibition were observed. PMID:25981932

  5. The impact of disease activity and tumour necrosis factor-α inhibitor therapy on cytokine levels in juvenile idiopathic arthritis.

    PubMed

    Walters, H M; Pan, N; Lehman, T J A; Adams, A; Kalliolias, G D; Zhu, Y S; Santiago, F; Nguyen, J; Sitaras, L; Cunningham-Rundles, S; Walsh, T J; Toussi, S S

    2016-06-01

    The aim of this study was to evaluate prospectively cytokine levels and disease activity in juvenile idiopathic arthritis (JIA) patients treated with and without tumour necrosis factor (TNF)-α inhibitors. TNF-α inhibitor-naive JIA subjects were followed prospectively for 6 months. Cytokine levels of TNF-α, interleukin (IL)-1β, IL-6, IL-8, IL-10 and IL-17 were measured at baseline for JIA subjects and healthy controls (HCs). Cytokine levels were then measured at four time-points after initiation of TNF-α inhibition for anti-TNF-α-treated (anti-TNF) JIA subjects, and at two subsequent time-points for other JIA (non-TNF) subjects. JIA disease activity by Childhood Health Assessment Questionnaire (CHAQ) disability index/pain score and physician joint count/global assessment was recorded. Sixteen anti-TNF, 31 non-TNF and 16 HCs were analysed. Among JIA subjects, those with higher baseline disease activity (subsequent anti-TNFs) had higher baseline TNF-α, IL-6 and IL-8 than those with lower disease activity (non-TNFs) (P < 0·05). TNF-α and IL-10 increased, and IL-6 and IL-8 no longer remained significantly higher after TNF-α inhibitor initiation in anti-TNF subjects. Subgroup analysis of etanercept versus adalimumab-treated subjects showed that TNF-α and IL-17 increased significantly in etanercept but not adalimumab-treated subjects, despite clinical improvement in both groups of subjects. JIA subjects with increased disease activity at baseline had higher serum proinflammatory cytokines. TNF-α inhibition resulted in suppression of IL-6 and IL-8 in parallel with clinical improvement in all anti-TNF-treated subjects, but was also associated with elevated TNF-α and IL-17 in etanercept-treated subjects. PMID:26934060

  6. Housing temperature-induced stress drives therapeutic resistance in murine tumour models through β2-adrenergic receptor activation

    NASA Astrophysics Data System (ADS)

    Eng, Jason W.-L.; Reed, Chelsey B.; Kokolus, Kathleen M.; Pitoniak, Rosemarie; Utley, Adam; Bucsek, Mark J.; Ma, Wen Wee; Repasky, Elizabeth A.; Hylander, Bonnie L.

    2015-03-01

    Cancer research relies heavily on murine models for evaluating the anti-tumour efficacy of therapies. Here we show that the sensitivity of several pancreatic tumour models to cytotoxic therapies is significantly increased when mice are housed at a thermoneutral ambient temperature of 30 °C compared with the standard temperature of 22 °C. Further, we find that baseline levels of norepinephrine as well as the levels of several anti-apoptotic molecules are elevated in tumours from mice housed at 22 °C. The sensitivity of tumours to cytotoxic therapies is also enhanced by administering a β-adrenergic receptor antagonist to mice housed at 22 °C. These data demonstrate that standard housing causes a degree of cold stress sufficient to impact the signalling pathways related to tumour-cell survival and affect the outcome of pre-clinical experiments. Furthermore, these data highlight the significant role of host physiological factors in regulating the sensitivity of tumours to therapy.

  7. Housing temperature-induced stress drives therapeutic resistance in murine tumour models through β2-adrenergic receptor activation

    PubMed Central

    Eng, Jason W.-L.; Reed, Chelsey B.; Kokolus, Kathleen M.; Pitoniak, Rosemarie; Utley, Adam; Bucsek, Mark J.; Ma, Wen Wee; Repasky, Elizabeth A.; Hylander, Bonnie L.

    2015-01-01

    Cancer research relies heavily on murine models for evaluating the anti-tumour efficacy of therapies. Here we show that the sensitivity of several pancreatic tumour models to cytotoxic therapies is significantly increased when mice are housed at a thermoneutral ambient temperature of 30 °C compared with the standard temperature of 22 °C. Further, we find that baseline levels of norepinephrine as well as the levels of several anti-apoptotic molecules are elevated in tumours from mice housed at 22 °C. The sensitivity of tumours to cytotoxic therapies is also enhanced by administering a β-adrenergic receptor antagonist to mice housed at 22 °C. These data demonstrate that standard housing causes a degree of cold stress sufficient to impact the signalling pathways related to tumour-cell survival and affect the outcome of pre-clinical experiments. Furthermore, these data highlight the significant role of host physiological factors in regulating the sensitivity of tumours to therapy. PMID:25756236

  8. Glutathione diminishes the anti-tumour activity of 4-hydroperoxycyclophosphamide by stabilising its spontaneous breakdown to alkylating metabolites.

    PubMed Central

    Lee, F. Y.

    1991-01-01

    Evidence was obtained showing that GSH protects against the cytotoxicity of 4-hydroperoxycyclophosphamide (4-OOH-CP) by minimizing the spontaneous fission of 4-hydroxycyclophosphamide (4-OH-CP), its breakdown product, to the ultimate toxic species, phosphoramide mustard (PM). This conclusion was borne out in two series of experiments. The first demonstrated that 4-OH-CP was progressively more stable in aqueous solutions containing increasing concentrations of GSH. The second series of experiments were carried out with tumour cell lines with high (SKOV-3) and low (KHT) GSH contents. The cytotoxicity of 4-OOH-CP, a stable precursor that rapidly gives rise to 4-OH-CP spontaneously under physiological conditions, was enhanced in GSH-depleted SKOV-3 cells, but was unchanged in GSH-depleted KHT cells. It is concluded that the high GSH content of SKOV-3 cells provides a significant protection against 4-OH-CP by limiting the breakdown/activation of 4-OH-CP. Deschloro-4-hydroperoxycyclophosphamide (deschloro-4-OOH-CP), an analogue of 4-OOH-CP that generates acrolein (AC) but not PM in the spontaneous fission reaction, is essentially non-toxic when compared with 4-OOH-CP but is equally potent in depleting GSH. It is postulated that AC may promote the cytotoxicity of the parent 4-OH-CP by depleting cellular GSH. Consequently, the stabilising influence of GSH on 4-OH-CP is removed, leading to increased formation of PM, the ultimate cytotoxic agent. PMID:1989664

  9. Relationships between tumour necrosis factor, eicosanoids and platelet-activating factor as mediators of endotoxin-induced shock in mice.

    PubMed Central

    Myers, A. K.; Robey, J. W.; Price, R. M.

    1990-01-01

    1. The toxicity of intravenous recombinant human tumour necrosis factor (rhTNF), a TNF fragment (TNF114-130), endotoxin and combinations of rhTNF or TNF114-130 were tested in mice. Neither rhTNF nor TNF114-130 was lethal alone, but when combined with a non-lethal dose of endotoxin, rhTNF provoked dose-dependent mortality, as did higher doses of endotoxin alone. 2. Both the toxicity and the vasopermeability changes induced by endotoxin alone were blocked by the platelet-activating factor (PAF) antagonist BN52021, indomethacin or the dual cyclo-oxygenase/lipoxygenase inhibitor BW755C. 3. The lethality of the combined low dose endotoxin/rhTNF challenge was unaffected by pretreatment with BN52021, indomethacin or BW755C, or by treatment at 6 h intervals with BN52021 or BW755C. 4. The results of these studies suggest that TNF, a putative, early mediator of septic or endotoxin shock, cannot by itself mimic all of the effects of bacterial endotoxin in the model used in this study. Apparently, TNF works synergistically with other mediators whose release is stimulated by endotoxin. 5. The results also suggest that the mechanism of shock production by the rhTNF/endotoxin combination in mice is not dependent on the early stimulation of eicosanoid or PAF synthesis by rhTNF. PMID:2110016

  10. Isolation and antiproliferative activity of Lotus corniculatus lectin towards human tumour cell lines.

    PubMed

    Rafiq, Shaista; Majeed, Rabiya; Qazi, Asif Khurshid; Ganai, Bashir Ahmad; Wani, Ishfak; Rakhshanda, Syed; Qurishi, Yasrib; Sharma, P R; Hamid, Abid; Masood, Akbar; Hamid, Rabia

    2013-12-15

    The objective of the study was to investigate the anti cancer activity of a lectin isolated from Lotus corniculatus seeds. A tetrameric 70kDa galactose specific lectin was purified using two step simple purification protocol which involved affinity chromatography on AF-BlueHC650M and gel filtration on Sephadex G-100. The lectin was adsorbed on AF-BlueHC650M and desorbed using 1M NaCl in the starting buffer. Gel filtration on Sephadex G-100 yielded a major peak absorbance that gave two bands of 15kDa and 20kDa in SDS PAGE. Hemagglutination activity was completely preserved, when the temperature was in the range of 20-60°C. However, drastic reduction in activity occurred at temperatures above 60°C. Full hemagglutination activity was retained at ambient pH 4-12. Thereafter no activity was observed above pH 13. Hemaglutination of the lectin was inhibited by d-galactose. The lectin showed a strong antiproliferative activity towards human leukemic (THP-1) cancer cells followed by lung cancer (HOP62) cells and HCT116 with an IC50 of 39μg/ml and 50μg/ml and 60μg/ml respectively. Flow cytometry analysis showed an increase in the percentage of cells in sub G0G1 phase confirming that Lotus corniculatus lectin induced apoptosis. Morphological observations showed that Lotus corniculatus lectin (LCL) treated THP-1 cells displayed apparent apoptosis characteristics such as nuclear fragmentation, appearance of membrane enclosed apoptotic bodies and DNA fragmentation. Lotus corniculatus lectin (LCL) effectively inhibits the cell migration in a dose dependent manner as indicated by the wound healing assay. PMID:24055517

  11. Characterisation of a cell swelling-activated K+-selective conductance of Ehrlich mouse ascites tumour cells

    PubMed Central

    Niemeyer, María Isabel; Hougaard, Charlotte; Hoffmann, Else K; Jørgensen, Finn; Stutzin, Andrés; Sepúlveda, Francisco V

    2000-01-01

    The K+ and Cl− currents activated by hypotonic cell swelling were studied in Ehrlich ascites tumour cells using the whole-cell recording mode of the patch-clamp technique. Currents were measured in the absence of added intracellular Ca2+ and with strong buffering of Ca2+. K+ current activated by cell swelling was measured as outward current at the Cl− equilibrium potential (ECl) under quasi-physiological gradients. It could be abolished by replacing extracellular Na+ with K+, thereby cancelling the driving force. Replacement with other cations suggested a selectivity sequence of K+ > Rb+ > NH4≈ Na+≈ Li+; Cs+ appeared to be inhibitory. The current-voltage relationship of the volume-sensitive K+ current was well fitted with the Goldman-Hodgkin-Katz current equation between -130 and +20 mV with a permeability coefficient of around 10−6 cm s−1 with both physiological and high-K+ extracellular solutions. The class III antiarrhythmic drug clofilium blocked the volume-sensitive K+ current in a voltage-independent manner with an IC50 of 32 μM. Clofilium was also found to be a strong inhibitor of the regulatory volume decrease response of Ehrlich cells. Cell swelling-activated K+ currents of Ehrlich cells are voltage and calcium insensitive and are resistant to a range of K+ channel inhibitors. These characteristics are similar to those of the so-called background K+ channels. Noise analysis of whole-cell current was consistent with a unitary conductance of 5.5 pS for the single channels underlying the K+ current evoked by cell swelling, measured at 0 mV under a quasi-physiological K+ gradient. PMID:10790156

  12. Dipeptidyl peptidase-4 activity might be a link between tumour necrosis factor alpha and insulin resistance in type 1 diabetes.

    PubMed

    Duvnjak, Lea; Blaslov, Kristina; Perković, Matea Nikolac; Ćuća, Jadranka Knežević

    2016-08-01

    Tumour necrosis factor alpha (TNF α) leads to β cell damage in type 1 diabetes (T1DM) but also causes insulin resistance (IR). It modulates dipeptidyl peptidase-4 (DPP-4) activity, adipokine linked with both IR and T1DM. We were interested if there is an association of TNF α in conjunction with DPP-4 and IR in T1DM. DPP-4 activity, TNF α concentration measurements, and insulin sensitivity calculation using estimated glucose disposal rate (eGDR) equation were performed in 70 T1DM patients. They were divided into two groups according to eGDR median. The group with higher IR had higher value of DPP-4 activity (27.57 ± 1.77 vs. 18.33 ± 1.14, p < 0.001) and TNF α concentration (12.91 ± 0.83 vs. 6.72 ± 0.36, p < 0.001). TNF α concentration and DPP-4 activity negatively correlated with eGDR (r = -0.616, p < 0.001 and r = -0.643, p < 0.001) while correlating positively with each other (r = 0.422; p = 0.001). The linear regression showed that eGDR decreases for 0.166 mg kg(-1) min(-1) by TNF α concentration increase of 1 pg/mL (p < 0.001) and for 0.090 mg kg(-1) min(-1) by DPP-4 activity increase of 1 U/L (p = 0.001) when adjusted for age, gender disease duration, glycated haemoglobin, body mass index and waist-to-hip ratio. eGDR decreased by additional 0.60 mg kg(-1) min(-1) (B = -0.150, p < 0.001) when DPP-4 activity was additionally adjusted for TNF α. TNF α concentration is associated with IR, correlates with its severity and increases the drop in insulin sensitivity modulated by DPP-4 activity. Whether TNF α involvement in the insulin signalling pathway is mediated by DPP-4 activity needs to be further evaluated. PMID:26906712

  13. The siRNA cocktail targeting interleukin 10 receptor and transforming growth factor-β receptor on dendritic cells potentiates tumour antigen-specific CD8(+) T cell immunity.

    PubMed

    Ahn, Y-H; Hong, S-O; Kim, J H; Noh, K H; Song, K-H; Lee, Y-H; Jeon, J-H; Kim, D-W; Seo, J H; Kim, T W

    2015-07-01

    Dendritic cells (DCs) are promising therapeutic agents in the field of cancer immunotherapy due to their intrinsic immune-priming capacity. The potency of DCs, however, is readily attenuated immediately after their administration in patients as tumours and various immune cells, including DCs, produce various immunosuppressive factors such as interleukin (IL)-10 and transforming growth factor (TGF)-β that hamper the function of DCs. In this study, we used small interfering RNA (siRNA) to silence the expression of endogenous molecules in DCs, which can sense immunosuppressive factors. Among the siRNAs targeting various immunosuppressive molecules, we observed that DCs transfected with siRNA targeting IL-10 receptor alpha (siIL-10RA) initiated the strongest antigen-specific CD8(+) T cell immune responses. The potency of siIL-10RA was enhanced further by combining it with siRNA targeting TGF-β receptor (siTGF-βR), which was the next best option during the screening of this study, or the previously selected immunoadjuvant siRNA targeting phosphatase and tensin homologue deleted on chromosome 10 (PTEN) or Bcl-2-like protein 11 (BIM). In the midst of sorting out the siRNA cocktails, the cocktail of siIL-10RA and siTGF-βR generated the strongest antigen-specific CD8(+) T cell immunity. Concordantly, the knock-down of both IL-10RA and TGF-βR in DCs induced the strongest anti-tumour effects in the TC-1 P0 tumour model, a cervical cancer model expressing the human papillomavirus (HPV)-16 E7 antigen, and even in the immune-resistant TC-1 (P3) tumour model that secretes more IL-10 and TGF-β than the parental tumour cells (TC-1 P0). These results provide the groundwork for future clinical development of the siRNA cocktail-mediated strategy by co-targeting immunosuppressive molecules to enhance the potency of DC-based vaccines. PMID:25753156

  14. Ligand substitutions between ruthenium–cymene compounds can control protein versus DNA targeting and anticancer activity

    PubMed Central

    Adhireksan, Zenita; Davey, Gabriela E.; Campomanes, Pablo; Groessl, Michael; Clavel, Catherine M.; Yu, Haojie; Nazarov, Alexey A.; Yeo, Charmian Hui Fang; Ang, Wee Han; Dröge, Peter; Rothlisberger, Ursula; Dyson, Paul J.; Davey, Curt A.

    2014-01-01

    Ruthenium compounds have become promising alternatives to platinum drugs by displaying specific activities against different cancers and favourable toxicity and clearance properties. Nonetheless, their molecular targeting and mechanism of action are poorly understood. Here we study two prototypical ruthenium-arene agents—the cytotoxic antiprimary tumour compound [(η6-p-cymene)Ru(ethylene-diamine)Cl]PF6 and the relatively non-cytotoxic antimetastasis compound [(η6-p-cymene)Ru(1,3,5-triaza-7-phosphaadamantane)Cl2]—and discover that the former targets the DNA of chromatin, while the latter preferentially forms adducts on the histone proteins. Using a novel ‘atom-to-cell’ approach, we establish the basis for the surprisingly site-selective adduct formation behaviour and distinct cellular impact of these two chemically similar anticancer agents, which suggests that the cytotoxic effects arise largely from DNA lesions, whereas the protein adducts may be linked to the other therapeutic activities. Our study shows promise for developing new ruthenium drugs, via ligand-based modulation of DNA versus protein binding and thus cytotoxic potential, to target distinguishing epigenetic features of cancer cells. PMID:24637564

  15. Therapy-induced tumour secretomes promote resistance and tumour progression

    PubMed Central

    Obenauf, Anna C.; Zou, Yilong; Ji, Andrew L.; Vanharanta, Sakari; Shu, Weiping; Shi, Hubing; Kong, Xiangju; Bosenberg, Marcus C.; Wiesner, Thomas; Rosen, Neal; Lo, Roger S.; Massagué, Joan

    2015-01-01

    Drug resistance invariably limits the clinical efficacy of targeted therapy with kinase inhibitors against cancer1,2. Here we show that targeted therapy with BRAF, ALK, or EGFR kinase inhibitors induces a complex network of secreted signals in drug-stressed melanoma and lung adenocarcinoma cells. This therapy-induced secretome (TIS) stimulates the outgrowth, dissemination, and metastasis of drug-resistant cancer cell clones and supports the survival of drug-sensitive cancer cells, contributing to incomplete tumour regression. The vemurafenib reactive secretome in melanoma is driven by down-regulation of the transcription factor FRA1. In situ transcriptome analysis of drug-resistant melanoma cells responding to the regressing tumour microenvironment revealed hyperactivation of multiple signalling pathways, most prominently the AKT pathway. Dual inhibition of RAF and PI3K/AKT/mTOR pathways blunted the outgrowth of the drug-resistant cell population in BRAF mutant melanoma tumours, suggesting this combination therapy as a strategy against tumour relapse. Thus, therapeutic inhibition of oncogenic drivers induces vast secretome changes in drug-sensitive cancer cells, paradoxically establishing a tumour microenvironment that supports the expansion of drug-resistant clones, but is susceptible to combination therapy. PMID:25807485

  16. Endopolyploidy in irradiated p53-deficient tumour cell lines: Persistence of cell division activity in giant cells expressing Aurora B- kinase

    PubMed Central

    Erenpreisa, Jekaterina; Ivanov, Andrei; Wheatley, Sally P; Kosmacek, Elizabeth A; Ianzini, Fiorenza; Anisimov, Alim P; Mackey, Michael; Davis, Paul J; Plakhins, Grigorijs; Illidge, Timothy M

    2008-01-01

    Recent findings including computerized live imaging suggest that polyploidy cells transiently emerging after severe genotoxic stress (and named ‘endopolyploid cells’) may have a role in tumour regrowth after anti-cancer treatment. Until now, mostly the factors enabling metaphase were studied in them. Here we investigate the mitotic activities and the role of Aurora B, in view of potential de-polyploidisation of these cells, because Aurora B- kinase is responsible for coordination and completion of mitosis. We observed that endopolyploid giant cells are formed in irradiated p53 tumours in several ways: (1) by division/fusion of daughter cells creating early multi-nucleated cells; (2) by asynchronous division/fusion of sub-nuclei of these multinucleated cells; (3) by a series of polyploidising mitoses reverting replicative interphase from aborted metaphase and forming giant cells with a single nucleus; (4) by micronucleation of arrested metaphases enclosing genome fragments; or (5) by incomplete division in the multipolar mitoses forming late multi-nucleated giant cells. We also observed that these activities are able to release para-diploid cells, although they do so infrequently. Although after a substantial delay, apoptosis typically occurs in these cells, we also found that roughly 2% of endopolyploid cells evade apoptosis and senescence arrest and continue mitotic activities. In this article we describe that catalytically active aurora B-kinase is expressed in the nuclei of many interphase endopolyploid cells, as well as being present at the centromeres, mitotic spindle and cleavage furrow during their mitotic efforts. The totally micronucleated giant cells (containing subgenomic fragments in multiple micronuclei) represented the only minor fraction, which failed to undergo mitosis and Aurora B was absent from it. These observations suggest that most endopolyploid tumour cells are not reproductively inert and that aurora B may contribute to the establishment

  17. Pyruvate dehydrogenase complex of ascites tumour. Activation by AMP and other properties of potential significance in metabolic regulation.

    PubMed Central

    Lazo, P A; Sols, A

    1980-01-01

    1. AMP is an activator of the pyruvate dehydrogenase complex of the Ehrlich--Lettré ascites tumour, increasing its V up to 2-fold, with Ka of 40 microM at pH 7.4. This activation appears to be an allosteric effect on the decarboxylase subunit of the complex. 2. The pyruvate dehydrogenase complex has a Km for pyruvate within the range 17--36 microM depending on the pH, the optimum pH being approx. 7.4, with a V of approx. 0.1 unit/g of cells. The rate-limiting step is dependent on the transformation of the enzyme--substrate complex. The Km for CoA is 15 microM. The Km for NAD+ is 0.7 mM for both the complex and the lipoamide dehydrogenase. The complex is inhibited by acetyl-CoA competitively with CoA; the Ki is 60 microM. The lipoamide dehydrogenase is inhibited by NADH and NADPH competitively with NAD+, with Ki values of 80 and 90 microM respectively. In the reverse reaction the Km values for NADH and NADPH are essentially equal to their Ki values for the forward reaction, the V for the latter being 0.09 of that of the former. Hence the reaction rate of the complex in vivo is likely to be markedly affected by feedback isosteric inhibition by reduced nicotinamide nucleotides and possibly acetyl-CoA. PMID:7193456

  18. Preparation and Anti-Tumour Activity of Some Arylbismuth(III) Oxine Complexes.

    PubMed

    Smith, K A; Deacon, G B; Jackson, W R; Tiekink, E R; Rainone, S; Webster, L K

    1998-01-01

    New arylbismuth(lll) oxinates, PhBi(MeOx)(2), (p-MeC(6)H(4))Bi(Ox)(2), (p-MeC(6)H(4))Bi(MeOx)(2), (p-ClC(6)H(4))Bi(Ox)(2), and (p-ClC(6)H(4))Bi(MeOx)(2) (Ox(-) = quinolin-8-olate and MeOx(-)=2-methylquinolin-8-olate) have been prepared by reaction of the appropriate diarylbismuth chlorides with Na(Ox) or Na(MeOx) in the presence of 15-crown-5. An X-ray crystallographic study has shown PhBi(MeOx)(2) to be a five coordinate monomer with distorted square pyramidal stereochemistry. Chelating MeOx ligands have a cisoid arrangement in the square plane and the phenyl group is apical. The lattice is stabilised by significant pi-pi interactions between centrosymmetric molecules. A range of these complexes has been shown to have high in vitro biological activity (comparable with or better than cisplatin) against L1210 leukaemia, the corresponding cisplatin resistant line, and a human ovarian cell line, SKOV-3. However, initial in vivo testing against a solid mouse plasmacytoma (PC6) and P388 leukaemia has not revealed significant activity. PMID:18475861

  19. Camera calibration approach based on adaptive active target

    NASA Astrophysics Data System (ADS)

    Zhang, Yalin; Zhou, Fuqiang; Deng, Peng

    2011-12-01

    Aiming at calibrating camera on site, where the lighting condition is hardly controlled and the quality of target images would be declined when the angle between camera and target changes, an adaptive active target is designed and the camera calibration approach based on the target is proposed. The active adaptive target in which LEDs are embedded is flat, providing active feature point. Therefore the brightness of the feature point can be modified via adjusting the electricity, judging from the threshold of image feature criteria. In order to extract features of the image accurately, the concept of subpixel-precise thresholding is also proposed. It converts the discrete representation of the digital image to continuous function by bilinear interpolation, and the sub-pixel contours are acquired by the intersection of the continuous function and the appropriate selection of threshold. According to analysis of the relationship between the features of the image and the brightness of the target, the area ratio of convex hulls and the grey value variance are adopted as the criteria. Result of experiments revealed that the adaptive active target accommodates well to the changing of the illumination in the environment, the camera calibration approach based on adaptive active target can obtain high level of accuracy and fit perfectly for image targeting in various industrial sites.

  20. Nuclease Target Site Selection for Maximizing On-target Activity and Minimizing Off-target Effects in Genome Editing.

    PubMed

    Lee, Ciaran M; Cradick, Thomas J; Fine, Eli J; Bao, Gang

    2016-03-01

    The rapid advancement in targeted genome editing using engineered nucleases such as ZFNs, TALENs, and CRISPR/Cas9 systems has resulted in a suite of powerful methods that allows researchers to target any genomic locus of interest. A complementary set of design tools has been developed to aid researchers with nuclease design, target site selection, and experimental validation. Here, we review the various tools available for target selection in designing engineered nucleases, and for quantifying nuclease activity and specificity, including web-based search tools and experimental methods. We also elucidate challenges in target selection, especially in predicting off-target effects, and discuss future directions in precision genome editing and its applications. PMID:26750397

  1. Nuclease Target Site Selection for Maximizing On-target Activity and Minimizing Off-target Effects in Genome Editing

    PubMed Central

    Lee, Ciaran M; Cradick, Thomas J; Fine, Eli J; Bao, Gang

    2016-01-01

    The rapid advancement in targeted genome editing using engineered nucleases such as ZFNs, TALENs, and CRISPR/Cas9 systems has resulted in a suite of powerful methods that allows researchers to target any genomic locus of interest. A complementary set of design tools has been developed to aid researchers with nuclease design, target site selection, and experimental validation. Here, we review the various tools available for target selection in designing engineered nucleases, and for quantifying nuclease activity and specificity, including web-based search tools and experimental methods. We also elucidate challenges in target selection, especially in predicting off-target effects, and discuss future directions in precision genome editing and its applications. PMID:26750397

  2. Targeted, noninvasive blockade of cortical neuronal activity

    NASA Astrophysics Data System (ADS)

    McDannold, Nathan; Zhang, Yongzhi; Power, Chanikarn; Arvanitis, Costas D.; Vykhodtseva, Natalia; Livingstone, Margaret

    2015-11-01

    Here we describe a novel method to noninvasively modulate targeted brain areas through the temporary disruption of the blood-brain barrier (BBB) via focused ultrasound, enabling focal delivery of a neuroactive substance. Ultrasound was used to locally disrupt the BBB in rat somatosensory cortex, and intravenous administration of GABA then produced a dose-dependent suppression of somatosensory-evoked potentials in response to electrical stimulation of the sciatic nerve. No suppression was observed 1-5 days afterwards or in control animals where the BBB was not disrupted. This method has several advantages over existing techniques: it is noninvasive; it is repeatable via additional GABA injections; multiple brain regions can be affected simultaneously; suppression magnitude can be titrated by GABA dose; and the method can be used with freely behaving subjects. We anticipate that the application of neuroactive substances in this way will be a useful tool for noninvasively mapping brain function, and potentially for surgical planning or novel therapies.

  3. Caffeic acid-coated multifunctional magnetic nanoparticles for the treatment and bimodal imaging of tumours.

    PubMed

    Lee, Jun; Kim, Kyoung Sub; Na, Kun

    2016-07-01

    Accurate theragnosis of tumour is essential for improving the life rate of tumour patients. Superparamagnetic iron oxide nanoparticles (SPIONs) have been used as both diagnostic and therapeutic agents. However, their application is often limited because of a lack of water solubility, lack of cancer treatment efficacy, and ineffective targeting of tumour cells. In this report, a double ligand (caffeic acid-polyethylene glycol-folic acid; FA-PEG-CA, caffeic acid-polyethylene glycol-pheophorbide-a; PheoA-PEG-CA) coated iron oxide nanoparticle has been fabricated that overcomes the limitations of conventional SPION. Photosensitizer and tumour targeting ligands were coated on SPION using a ligand-substitution method. We confirmed the successful substitution of oleic acid ligands with FA-PEG-CA and PheoA-PEG-CA ligands by FT-IR spectroscopy. The caffeic acid coated iron oxide nanoparticles (CAMNPs) also demonstrated high water solubility in an aqueous environment and folate-mediated active tumour targeting. The water solubility of CAMNPs was evaluated by DLS measurement and TEM images. The cytotoxicity of CAMNPs increased two-fold in MDA-MB-231 cells at a laser irradiation condition. The fabricated CAMNPs retained their ability to function as both MRI diagnostic and tumour-selective therapeutic agents. These results suggest that these efficient characteristics of CAMNPs can be incorporated into applications, thus enhancing the efficacy of clinical cancer treatment. PMID:27107705

  4. Tumour exosome integrins determine organotropic metastasis.

    PubMed

    Hoshino, Ayuko; Costa-Silva, Bruno; Shen, Tang-Long; Rodrigues, Goncalo; Hashimoto, Ayako; Tesic Mark, Milica; Molina, Henrik; Kohsaka, Shinji; Di Giannatale, Angela; Ceder, Sophia; Singh, Swarnima; Williams, Caitlin; Soplop, Nadine; Uryu, Kunihiro; Pharmer, Lindsay; King, Tari; Bojmar, Linda; Davies, Alexander E; Ararso, Yonathan; Zhang, Tuo; Zhang, Haiying; Hernandez, Jonathan; Weiss, Joshua M; Dumont-Cole, Vanessa D; Kramer, Kimberly; Wexler, Leonard H; Narendran, Aru; Schwartz, Gary K; Healey, John H; Sandstrom, Per; Labori, Knut Jørgen; Kure, Elin H; Grandgenett, Paul M; Hollingsworth, Michael A; de Sousa, Maria; Kaur, Sukhwinder; Jain, Maneesh; Mallya, Kavita; Batra, Surinder K; Jarnagin, William R; Brady, Mary S; Fodstad, Oystein; Muller, Volkmar; Pantel, Klaus; Minn, Andy J; Bissell, Mina J; Garcia, Benjamin A; Kang, Yibin; Rajasekhar, Vinagolu K; Ghajar, Cyrus M; Matei, Irina; Peinado, Hector; Bromberg, Jacqueline; Lyden, David

    2015-11-19

    Ever since Stephen Paget's 1889 hypothesis, metastatic organotropism has remained one of cancer's greatest mysteries. Here we demonstrate that exosomes from mouse and human lung-, liver- and brain-tropic tumour cells fuse preferentially with resident cells at their predicted destination, namely lung fibroblasts and epithelial cells, liver Kupffer cells and brain endothelial cells. We show that tumour-derived exosomes uptaken by organ-specific cells prepare the pre-metastatic niche. Treatment with exosomes from lung-tropic models redirected the metastasis of bone-tropic tumour cells. Exosome proteomics revealed distinct integrin expression patterns, in which the exosomal integrins α6β4 and α6β1 were associated with lung metastasis, while exosomal integrin αvβ5 was linked to liver metastasis. Targeting the integrins α6β4 and αvβ5 decreased exosome uptake, as well as lung and liver metastasis, respectively. We demonstrate that exosome integrin uptake by resident cells activates Src phosphorylation and pro-inflammatory S100 gene expression. Finally, our clinical data indicate that exosomal integrins could be used to predict organ-specific metastasis. PMID:26524530

  5. Tumour exosome integrins determine organotropic metastasis

    PubMed Central

    Hoshino, Ayuko; Costa-Silva, Bruno; Shen, Tang-Long; Rodrigues, Goncalo; Hashimoto, Ayako; Mark, Milica Tesic; Molina, Henrik; Kohsaka, Shinji; Di Giannatale, Angela; Ceder, Sophia; Singh, Swarnima; Williams, Caitlin; Soplop, Nadine; Uryu, Kunihiro; Pharmer, Lindsay; King, Tari; Bojmar, Linda; Davies, Alexander E.; Ararso, Yonathan; Zhang, Tuo; Zhang, Haiying; Hernandez, Jonathan; Weiss, Joshua M.; Dumont-Cole, Vanessa D.; Kramer, Kimberly; Wexler, Leonard H.; Narendran, Aru; Schwartz, Gary K.; Healey, John H.; Sandstrom, Per; Labori, Knut Jørgen; Kure, Elin H.; Grandgenett, Paul M.; Hollingsworth, Michael A.; de Sousa, Maria; Kaur, Sukhwinder; Jain, Maneesh; Mallya, Kavita; Batra, Surinder K.; Jarnagin, William R.; Brady, Mary S.; Fodstad, Oystein; Muller, Volkmar; Pantel, Klaus; Minn, Andy J.; Bissell, Mina J.; Garcia, Benjamin A.; Kang, Yibin; Rajasekhar, Vinagolu K.; Ghajar, Cyrus M.; Matei, Irina; Peinado, Hector; Bromberg, Jacqueline; Lyden, David

    2015-01-01

    Ever since Stephen Paget’s 1889 hypothesis, metastatic organotropism has remained one of cancer’s greatest mysteries. Here we demonstrate that exosomes from mouse and human lung-, liver- and brain-tropic tumour cells fuse preferentially with resident cells at their predicted destination, namely lung fibroblasts and epithelial cells, liver Kupffer cells and brain endothelial cells. We show that tumour-derived exosomes uptaken by organ-specific cells prepare the pre-metastatic niche. Treatment with exosomes from lung-tropic models redirected the metastasis of bone-tropic tumour cells. Exosome proteomics revealed distinct integrin expression patterns, in which the exosomal integrins α6β4 and α6β1 were associated with lung metastasis, while exosomal integrin αvβ5 was linked to liver metastasis. Targeting the integrins α6β4 and αvβ5 decreased exosome uptake, as well as lung and liver metastasis, respectively. We demonstrate that exosome integrin uptake by resident cells activates Src phosphorylation and pro-inflammatory S100 gene expression. Finally, our clinical data indicate that exosomal integrins could be used to predict organ-specific metastasis. PMID:26524530

  6. Distribution of Photofrin between tumour cells and tumour associated macrophages.

    PubMed Central

    Korbelik, M.; Krosl, G.; Olive, P. L.; Chaplin, D. J.

    1991-01-01

    Photofrin levels in cells derived from SCCVII tumours, excised from mice that previously received the drug, were measured using a fluorescence activated cell sorter (FACS). Concomitantly, in the same cells the FACS was used to measure fluorescein isothiocyanate (FITC) fluorescence that originated from FITC-conjugated antimouse IgG added to the cell suspension before sorting. This later measurement enabled discrimination between IgG negative tumour malignant cells and IgG positive host cells (primarily macrophages). In addition, cellular Photofrin content in 'tumour' and 'host' cells sorted by FACS was determined by chemical extraction. The measurements were performed for the time intervals 1-96 h post Photofrin administration. The data showed consistently higher Photofrin levels in the 'host cells', i.e., tumour associated macrophages (TAM), than in 'tumour' cells. On a per cell basis, at any time point studied there was a minimum of 1.7 times more Photofrin in 'host' than in 'tumour cells', while at 4-12 h postadministration, ratios of up to 3.0 times were observed. This corresponds to ratio values greater than 9, when based on Photofrin content per micrograms cell protein. PMID:1832927

  7. Dihomo-gamma-linolenic acid inhibits tumour necrosis factor-alpha production by human leucocytes independently of cyclooxygenase activity.

    PubMed

    Dooper, Maaike M B W; van Riel, Boet; Graus, Yvo M F; M'Rabet, Laura

    2003-11-01

    Dietary oils (such as borage oil), which are rich in gamma-linolenic acid (GLA), have been shown to be beneficial under inflammatory conditions. Dihomo-GLA (DGLA) is synthesized directly from GLA and forms a substrate for cyclooxygenase (COX) enzymes, resulting in the synthesis of lipid mediators (eicosanoids). In the present study, the immunomodulatory effects of DGLA were investigated and compared with those of other relevant fatty acids. Freshly isolated human peripheral blood mononuclear cells (PBMC) were cultured in fatty acid (100 microm)-enriched medium for 48 hr. Subsequently, cells were stimulated with lipopolysaccharide (LPS) for 20 hr and the cytokine levels were measured, in supernatants, by enzyme-linked immunosorbent assay (ELISA). Phospholipids were analysed by gas chromatography. Fatty acids were readily taken up, metabolized and incorporated into cellular phospholipids. Compared with the other fatty acids tested, DGLA exerted pronounced modulatory effects on cytokine production. Tumour necrosis factor-alpha (TNF-alpha) and interleukin (IL)-10 levels were reduced to 60% of control levels, whereas IL-6 levels were not affected by DGLA. Kinetic studies showed that peak levels of TNF-alpha, occurring early after LPS addition, were inhibited strongly, whereas IL-10 levels were not affected until 15 hr after stimulation. Both the reduction of cytokine levels and the decrease in arachidonic acid levels in these cells, induced by DGLA, were dose dependent, suggesting a shift in eicosanoid-subtype synthesis. However, although some DGLA-derived eicosanoids similarly reduced TNF-alpha levels, the effects of DGLA were probably not mediated by COX products, as the addition of indomethacin did not alter the effects of DGLA. In conclusion, these results suggest that DGLA affects cytokine production by human PBMC independently of COX activation. PMID:14632663

  8. Involvement of platelet-activating factor and tumour necrosis factor in the pathogenesis of joint inflammation in rabbits.

    PubMed Central

    Zarco, P; Maestre, C; Herrero-Beaumont, G; González, E; Garcia-Hoyo, R; Navarro, F J; Braquet, P; Egido, J

    1992-01-01

    We have studied the participation of platelet-activating factor (PAF) in antigen-induced arthritis in rabbits, as well as the possible co-operation between PAF and tumour necrosis factor (TNF) in their ability to induce joint inflammation when injected into the knees of healthy rabbits. The administration of two structurally different PAF receptor antagonists, BN52021 and Alprazolam, from 4 h before the intra-articular injection of ovalbumin in preimmunized rabbits, induced an important reduction in the synovial fluid volume, in the amount of cells infiltrating the articular cavity and the synovial membrane, as well as in the prostaglandin E2 (PGE2) concentration. Furthermore, proteoglycans of the articular cartilage, which were found diminished in animals with non-treated arthritis, were well preserved in rabbits treated with PAF antagonists. All the synovial fluids from joints with arthritis had detectable amounts of PAF. The injection of either TNF or PAF into the joints of normal rabbits induced a mild inflammation. When TNF was administered 1 h before PAF, a synergistic response was noted in the synovial fluid volume, in the accumulation of leucocytes, and in the amount of PGE2. The administration of BN50726, a hetrazepine with a potent PAF-receptor antagonist effect, induced a diminution in those parameters. Our results suggest that PAF may be an early and important mediator of joint damage, and that TNF can amplify the inflammatory response induced by PAF. PAF receptor antagonists could play some role in the treatment of inflammatory joint diseases. Images Fig. 2 Fig. 4 PMID:1315229

  9. Anti-tumour-promoting and thermal-induced protein denaturation inhibitory activities of β-sitosterol and lupeol isolated from Diospyros lotus L.

    PubMed

    Rauf, Abdur; Uddin, Ghias; Khan, Haroon; Raza, Muslim; Zafar, Muhammad; Tokuda, Harukuni

    2016-01-01

    In this study, the anti-tumour-promoting and thermal-induced protein denaturation inhibitory activities of β-sitosterol (1) and lupeol (2), isolated from Diospyros lotus L., were explored. Compound 1 showed a marked concentration-dependent inhibition against 12-O-tetradecanoylphorbol-13-acetate (20 ng/32 pmol)-induced Epstein-Barr virus early antigen activation in Raji cells with IC50 of 270 μg/ml, without significant toxicity (70% viability). Compound 2 showed significant anti-tumour-promoting effect with IC50 of 412 μg/ml, without significant toxicity (60% viability). In heat-induced protein denaturation assay, compound 1 exhibited a concentration-dependent attenuation with a maximum effect of 73.5% at 500 μg/ml with EC50 of 117 μg/ml, while compound 2 exhibited a maximum effect of 59.2% at 500 μg/ml with EC50 of 355 μg/ml. Moreover, in silico docking studies against the phosphoinositide 3-kinase enzyme also show the inhibitory potency of these compounds. In short, both the compounds exhibited a marked anti-tumour-promoting and potent inhibitory effect on thermal-induced protein denaturation. PMID:26134930

  10. Activation of p53 Facilitates the Target Search in DNA by Enhancing the Target Recognition Probability.

    PubMed

    Itoh, Yuji; Murata, Agato; Sakamoto, Seiji; Nanatani, Kei; Wada, Takehiko; Takahashi, Satoshi; Kamagata, Kiyoto

    2016-07-17

    Tumor suppressor p53 binds to the target in a genome and regulates the expression of downstream genes. p53 searches for the target by combining three-dimensional diffusion and one-dimensional sliding along the DNA. To examine the regulation mechanism of the target binding, we constructed the pseudo-wild type (pseudo-WT), activated (S392E), and inactive (R248Q) mutants of p53 and observed their target binding in long DNA using single-molecule fluorescence imaging. The pseudo-WT sliding along the DNA showed many pass events over the target and possessed target recognition probability (TRP) of 7±2%. The TRP increased to 18±2% for the activated mutant but decreased to 0% for the inactive mutant. Furthermore, the fraction of the target binding by the one-dimensional sliding among the total binding events increased from 63±9% for the pseudo-WT to 87±2% for the activated mutant. Control of TRP upon activation, as demonstrated here for p53, might be a general activation mechanism of transcription factors. PMID:27291286

  11. A non-aggregated and tumour-associated macrophage-targeted photosensitiser for photodynamic therapy: a novel zinc(II) phthalocyanine containing octa-sulphonates.

    PubMed

    Li, Xing-Shu; Ke, Mei-Rong; Zhang, Miao-Fen; Tang, Qing-Qing; Zheng, Bi-Yuan; Huang, Jian-Dong

    2015-03-18

    A novel zinc(II) phthalocyanine bearing octa-sulphonates has been prepared, which is non-aggregated in water, highly photoactive and low dark-toxic. More interestingly, it exhibits specific affinity to macrophages via the scavenger receptor-A, and can selectively accumulate in tumour sites. PMID:25692672

  12. FRA-1 as a driver of tumour heterogeneity: a nexus between oncogenes and embryonic signalling pathways in cancer.

    PubMed

    Dhillon, A S; Tulchinsky, E

    2015-08-20

    Tumour heterogeneity is a major factor undermining the success of therapies targeting metastatic cancer. Two major theories are thought to explain the phenomenon of heterogeneity in cancer--clonal evolution and cell plasticity. In this review, we examine a growing body of work implicating the transcription factor FOS-related antigen 1 (FRA-1) as a central node in tumour cell plasticity networks, and discuss mechanisms regulating its activity in cancer cells. We also discuss evidence from the FRA-1 perspective supporting the notion that clonal selection and cell plasticity represent two sides of the same coin. We propose that FRA-1-overexpressing clones featuring high plasticity undergo positive selection during consecutive stages of multistep tumour progression. This model underscores a potential mechanism through which tumour cells retaining elevated levels of plasticity acquire a selective advantage over other clonal populations within a tumour. PMID:25381818

  13. An update on molecular genetics of gastrointestinal stromal tumours

    PubMed Central

    Tornillo, L; Terracciano, L M

    2006-01-01

    Gastrointestinal stromal tumours (GISTs) are the most common primary mesenchymal tumours of the gastrointestinal tract. Most of them show activating mutations of the genes coding for KIT or platelet‐derived growth factor receptor α (PDGFRα), two receptor tyrosine kinases (RTKs). The RTK inhibitor Imatinib (Gleevec®, Novartis, Switzerland), induces regression of the tumour. The level of response to treatment, together with other clinicopathological parameters is related to the type and site of the activating mutation, thus suggesting that these tumours should be classified according to the molecular context. This is confirmed also by the phenomenon of the resistance to treatment, which arises because of different mechanisms (second mutation, amplification, activation of other RTKs) and can be fought only by specific RTK inhibitors, that are at present under development. RTK activation involves an homogeneous transduction pathway whose components (MAPK, AKT, PI3K, mTOR and RAS) are possible targets of new molecular treatment. A new paradigm of classification integrating the classic pathological criteria with the molecular changes will permit personalised prognosis and treatment. PMID:16731599

  14. Active calibration target for bistatic radar cross-section measurements

    NASA Astrophysics Data System (ADS)

    Pienaar, M.; Odendaal, J. W.; Joubert, J.; Cilliers, J. E.; Smit, J. C.

    2016-05-01

    Either passive calibration targets are expensive and complex to manufacture or their bistatic radar cross section (RCS) levels are significantly lower than the monostatic RCS levels of targets such as spheres, dihedral, and trihedral corner reflectors. In this paper the performance of an active calibration target with relative high bistatic RCS values is illustrated as a reference target for bistatic RCS measurements. The reference target is simple to manufacture, operates over a wide frequency range, and can be configured to calibrate all four polarizations (VV, HH, HV, and VH). Bistatic RCS measurements of canonical targets, performed in a controlled environment, are calibrated with the reference target and the results are compared to simulated results using FEKO.

  15. Effects of a cloned cell line with NK activity on bone marrow transplants, tumour development and metastasis in vivo

    NASA Astrophysics Data System (ADS)

    Warner, John F.; Dennert, Gunther

    1982-11-01

    Natural killer (NK) cells cloned in vitro have been transferred into NK-deficient hosts. These cells have been shown to have a role in the rejection of allogeneic bone marrow grafts, resistance to both radiation-induced thymic leukaemia and challenge with melanoma tumour cells. It appears that NK cells have an important role in immune surveillance.

  16. Decreased NK-cell tumour immunosurveillance consequent to JAK inhibition enhances metastasis in breast cancer models

    PubMed Central

    Bottos, Alessia; Gotthardt, Dagmar; Gill, Jason W.; Gattelli, Albana; Frei, Anna; Tzankov, Alexandar; Sexl, Veronika; Wodnar-Filipowicz, Aleksandra; Hynes, Nancy E.

    2016-01-01

    The JAK/STAT pathway is an attractive target for breast cancer therapy due to its frequent activation, and clinical trials evaluating JAK inhibitors (JAKi) in advanced breast cancer are ongoing. Using patient biopsies and preclinical models of breast cancer, we demonstrate that the JAK/STAT pathway is active in metastasis. Unexpectedly, blocking the pathway with JAKi enhances the metastatic burden in experimental and orthotopic models of breast cancer metastasis. We demonstrate that this prometastatic effect is due to the immunosuppressive activity of JAKi with ensuing impairment of NK-cell-mediated anti-tumour immunity. Furthermore, we show that immunostimulation with IL-15 overcomes the enhancing effect of JAKi on metastasis formation. Our findings highlight the importance of evaluating the effect of targeted therapy on the tumour environment. The impact of JAKi on NK cells and the potential value of immunostimulators to overcome the weakened tumour immunosurveillance, are worthwhile considering in the clinical setting of breast cancer. PMID:27406745

  17. Decreased NK-cell tumour immunosurveillance consequent to JAK inhibition enhances metastasis in breast cancer models.

    PubMed

    Bottos, Alessia; Gotthardt, Dagmar; Gill, Jason W; Gattelli, Albana; Frei, Anna; Tzankov, Alexandar; Sexl, Veronika; Wodnar-Filipowicz, Aleksandra; Hynes, Nancy E

    2016-01-01

    The JAK/STAT pathway is an attractive target for breast cancer therapy due to its frequent activation, and clinical trials evaluating JAK inhibitors (JAKi) in advanced breast cancer are ongoing. Using patient biopsies and preclinical models of breast cancer, we demonstrate that the JAK/STAT pathway is active in metastasis. Unexpectedly, blocking the pathway with JAKi enhances the metastatic burden in experimental and orthotopic models of breast cancer metastasis. We demonstrate that this prometastatic effect is due to the immunosuppressive activity of JAKi with ensuing impairment of NK-cell-mediated anti-tumour immunity. Furthermore, we show that immunostimulation with IL-15 overcomes the enhancing effect of JAKi on metastasis formation. Our findings highlight the importance of evaluating the effect of targeted therapy on the tumour environment. The impact of JAKi on NK cells and the potential value of immunostimulators to overcome the weakened tumour immunosurveillance, are worthwhile considering in the clinical setting of breast cancer. PMID:27406745

  18. Climacostol reduces tumour progression in a mouse model of melanoma via the p53-dependent intrinsic apoptotic programme

    PubMed Central

    Perrotta, Cristiana; Buonanno, Federico; Zecchini, Silvia; Giavazzi, Alessio; Proietti Serafini, Francesca; Catalani, Elisabetta; Guerra, Laura; Belardinelli, Maria Cristina; Picchietti, Simona; Fausto, Anna Maria; Giorgi, Simone; Marcantoni, Enrico; Clementi, Emilio; Ortenzi, Claudio; Cervia, Davide

    2016-01-01

    Climacostol, a compound produced by the ciliated protozoan Climacostomum virens, displayed cytotoxic properties in vitro. This study demonstrates that it has anti-tumour potential. Climacostol caused a reduction of viability/proliferation of B16-F10 mouse melanoma cells, a rapidly occurring DNA damage, and induced the intrinsic apoptotic pathway characterised by the dissipation of the mitochondrial membrane potential, the translocation of Bax to the mitochondria, the release of Cytochrome c from the mitochondria, and the activation of Caspase 9-dependent cleavage of Caspase 3. The apoptotic mechanism of climacostol was found to rely on the up-regulation of p53 and its targets Noxa and Puma. In vivo analysis of B16-F10 allografts revealed a persistent inhibition of tumour growth rate when melanomas were treated with intra-tumoural injections of climacostol. In addition, it significantly improved the survival of transplanted mice, decreased tumour weight, induced a remarkable reduction of viable cells inside the tumour, activated apoptosis and up-regulated the p53 signalling network. Importantly, climacostol toxicity was more selective against tumour than non-tumour cells. The anti-tumour properties of climacostol and the molecular events associated with its action indicate that it is a powerful agent that may be considered for the design of pro-apoptotic drugs for melanoma therapy. PMID:27271364

  19. Climacostol reduces tumour progression in a mouse model of melanoma via the p53-dependent intrinsic apoptotic programme.

    PubMed

    Perrotta, Cristiana; Buonanno, Federico; Zecchini, Silvia; Giavazzi, Alessio; Proietti Serafini, Francesca; Catalani, Elisabetta; Guerra, Laura; Belardinelli, Maria Cristina; Picchietti, Simona; Fausto, Anna Maria; Giorgi, Simone; Marcantoni, Enrico; Clementi, Emilio; Ortenzi, Claudio; Cervia, Davide

    2016-01-01

    Climacostol, a compound produced by the ciliated protozoan Climacostomum virens, displayed cytotoxic properties in vitro. This study demonstrates that it has anti-tumour potential. Climacostol caused a reduction of viability/proliferation of B16-F10 mouse melanoma cells, a rapidly occurring DNA damage, and induced the intrinsic apoptotic pathway characterised by the dissipation of the mitochondrial membrane potential, the translocation of Bax to the mitochondria, the release of Cytochrome c from the mitochondria, and the activation of Caspase 9-dependent cleavage of Caspase 3. The apoptotic mechanism of climacostol was found to rely on the up-regulation of p53 and its targets Noxa and Puma. In vivo analysis of B16-F10 allografts revealed a persistent inhibition of tumour growth rate when melanomas were treated with intra-tumoural injections of climacostol. In addition, it significantly improved the survival of transplanted mice, decreased tumour weight, induced a remarkable reduction of viable cells inside the tumour, activated apoptosis and up-regulated the p53 signalling network. Importantly, climacostol toxicity was more selective against tumour than non-tumour cells. The anti-tumour properties of climacostol and the molecular events associated with its action indicate that it is a powerful agent that may be considered for the design of pro-apoptotic drugs for melanoma therapy. PMID:27271364

  20. Tumour angiogenesis-Origin of blood vessels.

    PubMed

    Krishna Priya, S; Nagare, R P; Sneha, V S; Sidhanth, C; Bindhya, S; Manasa, P; Ganesan, T S

    2016-08-15

    The conventional view of tumour vascularization is that tumours acquire their blood supply from neighbouring normal stroma. Additional methods of tumour vascularization such as intussusceptive angiogenesis, vasculogenic mimicry, vessel co-option and vasculogenesis have been demonstrated to occur. However, the origin of the endothelial cells and pericytes in the tumour vasculature is not fully understood. Their origin from malignant cells has been shown indirectly in lymphoma and neuroblastoma by immuno-FISH experiments. It is now evident that tumours arise from a small population of cells called cancer stem cells (CSCs) or tumour initiating cells. Recent data suggest that a proportion of tumour endothelial cells arise from cancer stem cells in glioblastoma. This was demonstrated both in vitro and in vivo. The analysis of chromosomal abnormalities in endothelial cells showed identical genetic changes to those identified in tumour cells. However, another report contradicted these results from the earlier studies in glioblastoma and had shown that CSCs give rise to pericytes and not endothelial cells. The main thrust of this review is the critical analysis of the conflicting data from different studies and the remaining questions in this field of research. The mechanism by which this phenomenon occurs is also discussed in detail. The transdifferentiation of CSCs to endothelial cells/pericytes has many implications in the progression and metastasis of the tumours and hence it would be a novel target for antiangiogenic therapy. PMID:26934471

  1. Cancer active targeting by nanoparticles: a comprehensive review of literature

    PubMed Central

    Bazak, Remon; Houri, Mohamad; Achy, Samar El; Kamel, Serag

    2016-01-01

    Purpose Cancer is one of the leading causes of death, and thus, the scientific community has but great efforts to improve cancer management. Among the major challenges in cancer management is development of agents that can be used for early diagnosis and effective therapy. Conventional cancer management frequently lacks accurate tools for detection of early tumors and has an associated risk of serious side effects of chemotherapeutics. The need to optimize therapeutic ratio as the difference with which a treatment affects cancer cells versus healthy tissues lead to idea that it is needful to have a treatment that could act a the “magic bullet”—recognize cancer cells only. Nanoparticle platforms offer a variety of potentially efficient solutions for development of targeted agents that can be exploited for cancer diagnosis and treatment. There are two ways by which targeting of nanoparticles can be achieved, namely passive and active targeting. Passive targeting allows for the efficient localization of nanoparticles within the tumor microenvironment. Active targeting facilitates the active uptake of nanoparticles by the tumor cells themselves. Methods Relevant English electronic databases and scientifically published original articles and reviews were systematically searched for the purpose of this review. Results In this report, we present a comprehensive review of literatures focusing on the active targeting of nanoparticles to cancer cells, including antibody and antibody fragment-based targeting, antigen-based targeting, aptamer-based targeting, as well as ligand-based targeting. Conclusion To date, the optimum targeting strategy has not yet been announced, each has its own advantages and disadvantages even though a number of them have found their way for clinical application. Perhaps, a combination of strategies can be employed to improve the precision of drug delivery, paving the way for a more effective personalized therapy. PMID:25005786

  2. Development of a novel fluorogenic proteolytic beacon for in vivo detection and imaging of tumour-associated matrix metalloproteinase-7 activity.

    PubMed Central

    McIntyre, J Oliver; Fingleton, Barbara; Wells, K Sam; Piston, David W; Lynch, Conor C; Gautam, Shiva; Matrisian, Lynn M

    2004-01-01

    The present study describes the in vivo detection and imaging of tumour-associated MMP-7 (matrix metalloproteinase-7 or matrilysin) activity using a novel polymer-based fluorogenic substrate PB-M7VIS, which serves as a selective 'proteolytic beacon' (PB) for this metalloproteinase. PB-M7VIS is built on a PAMAM (polyamido amino) dendrimer core of 14.2 kDa, covalently coupled with an Fl (fluorescein)-labelled peptide Fl(AHX)RPLALWRS(AHX)C (where AHX stands for aminohexanoic acid) and with TMR (tetramethylrhodamine). PB-M7VIS is efficiently and selectively cleaved by MMP-7 with a k (cat)/ K (m) value of 1.9x10(5) M(-1).s(-1) as measured by the rate of increase in Fl fluorescence (up to 17-fold for the cleavage of an optimized PB-M7VIS) with minimal change in the TMR fluorescence. The K (m) value for PB-M7VIS is approx. 0.5 microM, which is approx. two orders of magnitude lower when compared with that for an analogous soluble peptide, indicating efficient interaction of MMP-7 with the synthetic polymeric substrate. With MMP-2 or -3, the k (cat)/ K (m) value for PB-M7VIS is approx. 56- or 13-fold lower respectively, when compared with MMP-7. In PB-M7VIS, Fl(AHX)RPLALWRS(AHX)C is a selective optical sensor of MMP-7 activity and TMR serves to detect both the uncleaved and cleaved reagents. Each of these can be visualized as subcutaneous fluorescent phantoms in a mouse and optically discriminated based on the ratio of green/red (Fl/TMR) fluorescence. The in vivo specificity of PB-M7VIS was tested in a mouse xenograft model. Intravenous administration of PB-M7VIS gave significantly enhanced Fl fluorescence from MMP-7-positive tumours, but not from control tumours ( P <0.0001), both originally derived from SW480 human colon cancer cells. Prior systemic treatment of the tumour-bearing mice with an MMP inhibitor BB-94 ([4-( N -hydroxyamino)-2 R -isobutyl-3 S -(thienylthiomethyl)-succinyl]-L-phenylalanine- N -methylamide), markedly decreased the Fl fluorescence over the MMP-7

  3. G9a inhibition potentiates the anti-tumour activity of DNA double-strand break inducing agents by impairing DNA repair independent of p53 status.

    PubMed

    Agarwal, Pallavi; Jackson, Stephen P

    2016-10-01

    Cancer cells often exhibit altered epigenetic signatures that can misregulate genes involved in processes such as transcription, proliferation, apoptosis and DNA repair. As regulation of chromatin structure is crucial for DNA repair processes, and both DNA repair and epigenetic controls are deregulated in many cancers, we speculated that simultaneously targeting both might provide new opportunities for cancer therapy. Here, we describe a focused screen that profiled small-molecule inhibitors targeting epigenetic regulators in combination with DNA double-strand break (DSB) inducing agents. We identify UNC0638, a catalytic inhibitor of histone lysine N-methyl-transferase G9a, as hypersensitising tumour cells to low doses of DSB-inducing agents without affecting the growth of the non-tumorigenic cells tested. Similar effects are also observed with another, structurally distinct, G9a inhibitor A-366. We also show that small-molecule inhibition of G9a or siRNA-mediated G9a depletion induces tumour cell death under low DNA damage conditions by impairing DSB repair in a p53 independent manner. Furthermore, we establish that G9a promotes DNA non-homologous end-joining in response to DSB-inducing genotoxic stress. This study thus highlights the potential for using G9a inhibitors as anti-cancer therapeutic agents in combination with DSB-inducing chemotherapeutic drugs such as etoposide. PMID:27431310

  4. Periostin promotes immunosuppressive premetastatic niche formation to facilitate breast tumour metastasis.

    PubMed

    Wang, Zhe; Xiong, Shanshan; Mao, Yubin; Chen, Mimi; Ma, Xiaohong; Zhou, Xueliang; Ma, Zhenling; Liu, Fan; Huang, Zhengjie; Luo, Qi; Ouyang, Gaoliang

    2016-08-01

    Periostin (POSTN) is a limiting factor in the metastatic colonization of disseminated tumour cells. However, the role of POSTN in regulating the immunosuppressive function of immature myeloid cells in tumour metastasis has not been documented. Here, we demonstrate that POSTN promotes the pulmonary accumulation of myeloid-derived suppressor cells (MDSCs) during the early stage of breast tumour metastasis. Postn deletion decreases neutrophil and monocytic cell populations in the bone marrow of mice and suppresses the accumulation of MDSCs to premetastatic sites. We also found that POSTN-deficient MDSCs display reduced activation of ERK, AKT and STAT3 and that POSTN deficiency decreases the immunosuppressive functions of MDSCs during tumour progression. Moreover, the pro-metastatic role of POSTN is largely limited to ER-negative breast cancer patients. Lysyl oxidase contributes to POSTN-promoted premetastatic niche formation and tumour metastasis. Our findings indicate that POSTN is essential for immunosuppressive premetastatic niche formation in the lungs during breast tumour metastasis and is a potential target for the prevention and treatment of breast tumour metastasis. Copyright © 2016 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. PMID:27193093

  5. Reprogramming of the tumour microenvironment by stromal PTEN-regulated miR-320.

    PubMed

    Bronisz, A; Godlewski, J; Wallace, J A; Merchant, A S; Nowicki, M O; Mathsyaraja, H; Srinivasan, R; Trimboli, A J; Martin, C K; Li, F; Yu, L; Fernandez, S A; Pécot, T; Rosol, T J; Cory, S; Hallett, M; Park, M; Piper, M G; Marsh, C B; Yee, L D; Jimenez, R E; Nuovo, G; Lawler, S E; Chiocca, E A; Leone, G; Ostrowski, M C

    2012-02-01

    PTEN (Phosphatase and tensin homolog deleted on chromosome 10) expression in stromal fibroblasts suppresses epithelial mammary tumours, but the underlying molecular mechanisms remain unknown. Using proteomic and expression profiling, we show that Pten loss from mammary stromal fibroblasts activates an oncogenic secretome that orchestrates the transcriptional reprogramming of other cell types in the microenvironment. Downregulation of miR-320 and upregulation of one of its direct targets, ETS2 (v-ets erythroblastosis virus E26 oncogene homolog 2) are critical events in Pten-deleted stromal fibroblasts responsible for inducing this oncogenic secretome, which in turn promotes tumour angiogenesis and tumour-cell invasion. Expression of the Pten-miR-320-Ets2-regulated secretome distinguished human normal breast stroma from tumour stroma and robustly correlated with recurrence in breast cancer patients. This work reveals miR-320 as a critical component of the Pten tumour-suppressor axis that acts in stromal fibroblasts to reprogramme the tumour microenvironment and curtail tumour progression. PMID:22179046

  6. Activation of p38 mitogen-activated protein kinase and nuclear factor-kappaB in tumour necrosis factor-induced eotaxin release of human eosinophils

    PubMed Central

    WONG, C K; ZHANG, J P; IP, W K; LAM, C W K

    2002-01-01

    The CC chemokine eotaxin is a potent eosinophil-specific chemoattractant that is crucial for allergic inflammation. Allergen-induced tumour necrosis factor (TNF) has been shown to induce eotaxin synthesis in eosinophils. Nuclear factor-kappaB (NF-κB) and mitogen-activated protein kinases (MAPK) have been found to play an essential role for the eotaxin-mediated eosinophilia. We investigated the modulation of NF-κB and MAPK activation in TNF-induced eotaxin release of human eosinophils. Human blood eosinophils were purified from fresh buffy coat using magnetic cell sorting. NF-κB pathway-related genes were evaluated by cDNA expression array system. Degradation of IκBα and phosphorylation of MAPK were detected by Western blot. Activation of NF-κB was determined by electrophoretic mobility shift assay. Eotaxin released into the eosinophil culture medium was measured by ELISA. TNF was found to up-regulate the gene expression of NF-κB and IκBα in eosinophils. TNF-induced IκBα degradation was inhibited by the proteasome inhibitor N-cbz-Leu-Leu-leucinal (MG-132) and a non-steroidal anti-inflammatory drug sodium salicylate (NaSal). Using EMSA, both MG-132 and NaSal were found to suppress the TNF-induced NF-κB activation in eosinophils. Furthermore, TNF was shown to induce phosphorylation of p38 MAPK time-dependently but not extracellular signal-regulated kinases (ERK). Inhibition of NF-κB activation and p38 MAPK activity decreased the TNF-induced release of eotaxin from eosinophils. These results indicate that NF-κB and p38 MAPK play an important role in TNF-activated signalling pathway regulating eotaxin release by eosinophils. They have also provided a biochemical basis for the potential of using specific inhibitors of NF-κB and p38 MAPK for treating allergic inflammation. PMID:12067303

  7. The Succinated Proteome of FH-Mutant Tumours.

    PubMed

    Yang, Ming; Ternette, Nicola; Su, Huizhong; Dabiri, Raliat; Kessler, Benedikt M; Adam, Julie; Teh, Bin Tean; Pollard, Patrick J

    2014-01-01

    Inherited mutations in the Krebs cycle enzyme fumarate hydratase (FH) predispose to hereditary leiomyomatosis and renal cell cancer (HLRCC). Loss of FH activity in HLRCC tumours causes accumulation of the Krebs cycle intermediate fumarate to high levels, which may act as an oncometabolite through various, but not necessarily mutually exclusive, mechanisms. One such mechanism, succination, is an irreversible non-enzymatic modification of cysteine residues by fumarate, to form S-(2-succino)cysteine (2SC). Previous studies have demonstrated that succination of proteins including glyceraldehyde 3-phosphate dehydrogenase (GAPDH), kelch-like ECH-associated protein 1 (KEAP1) and mitochondrial aconitase (ACO2) can have profound effects on cellular metabolism. Furthermore, immunostaining for 2SC is a sensitive and specific biomarker for HLRCC tumours. Here, we performed a proteomic screen on an FH-mutant tumour and two HLRCC-derived cancer cell lines and identified 60 proteins where one or more cysteine residues were succinated; 10 of which were succinated at cysteine residues either predicted, or experimentally proven, to be functionally significant. Bioinformatic enrichment analyses identified most succinated targets to be involved in redox signaling. To our knowledge, this is the first proteomic-based succination screen performed in human tumours and cancer-derived cells and has identified novel 2SC targets that may be relevant to the pathogenesis of HLRCC. PMID:25105836

  8. The Succinated Proteome of FH-Mutant Tumours

    PubMed Central

    Yang, Ming; Ternette, Nicola; Su, Huizhong; Dabiri, Raliat; Kessler, Benedikt M.; Adam, Julie; Teh, Bin Tean; Pollard, Patrick J.

    2014-01-01

    Inherited mutations in the Krebs cycle enzyme fumarate hydratase (FH) predispose to hereditary leiomyomatosis and renal cell cancer (HLRCC). Loss of FH activity in HLRCC tumours causes accumulation of the Krebs cycle intermediate fumarate to high levels, which may act as an oncometabolite through various, but not necessarily mutually exclusive, mechanisms. One such mechanism, succination, is an irreversible non-enzymatic modification of cysteine residues by fumarate, to form S-(2-succino)cysteine (2SC). Previous studies have demonstrated that succination of proteins including glyceraldehyde 3-phosphate dehydrogenase (GAPDH), kelch-like ECH-associated protein 1 (KEAP1) and mitochondrial aconitase (ACO2) can have profound effects on cellular metabolism. Furthermore, immunostaining for 2SC is a sensitive and specific biomarker for HLRCC tumours. Here, we performed a proteomic screen on an FH-mutant tumour and two HLRCC-derived cancer cell lines and identified 60 proteins where one or more cysteine residues were succinated; 10 of which were succinated at cysteine residues either predicted, or experimentally proven, to be functionally significant. Bioinformatic enrichment analyses identified most succinated targets to be involved in redox signaling. To our knowledge, this is the first proteomic-based succination screen performed in human tumours and cancer-derived cells and has identified novel 2SC targets that may be relevant to the pathogenesis of HLRCC. PMID:25105836

  9. The role of JAK/STAT signalling in the pathogenesis, prognosis and treatment of solid tumours

    PubMed Central

    Thomas, S J; Snowden, J A; Zeidler, M P; Danson, S J

    2015-01-01

    Aberrant activation of intracellular signalling pathways confers malignant properties on cancer cells. Targeting intracellular signalling pathways has been a productive strategy for drug development, with several drugs acting on signalling pathways already in use and more continually being developed. The JAK/STAT signalling pathway provides an example of this paradigm in haematological malignancies, with the identification of JAK2 mutations in myeloproliferative neoplasms leading to the development of specific clinically effective JAK2 inhibitors, such as ruxolitinib. It is now clear that many solid tumours also show activation of JAK/STAT signalling. In this review, we focus on the role of JAK/STAT signalling in solid tumours, examining the molecular mechanisms that cause inappropriate pathway activation and their cellular consequences. We also discuss the degree to which activated JAK/STAT signalling contributes to oncogenesis. Studies showing the effect of activation of JAK/STAT signalling upon prognosis in several tumour types are summarised. Finally, we discuss the prospects for treating solid tumours using strategies targeting JAK/STAT signalling, including what can be learned from haematological malignancies and the extent to which results in solid tumours might be expected to differ. PMID:26151455

  10. Association of tumour necrosis factor alpha and its receptors with thymidine phosphorylase expression in invasive breast carcinoma.

    PubMed Central

    Leek, R. D.; Landers, R.; Fox, S. B.; Ng, F.; Harris, A. L.; Lewis, C. E.

    1998-01-01

    Angiogenesis is an essential requirement for tumour growth and metastasis and is regulated by a complex network of factors produced by both stromal cells and neoplastic cells within solid tumours. The cytokine tumour necrosis factor alpha (TNF-alpha) and the enzyme thymidine phosphorylase (TP) are two factors known to promote tumour angiogenesis. We have demonstrated recently that high numbers of tumour-associated macrophages (TAMs) are significantly associated with increased tumour angiogenesis and poor prognosis in invasive carcinoma of the breast. We have also shown that TAMs are a major source of TNF-alpha in invasive breast carcinomas, and that macrophage-like stromal cells as well as tumour cells synthesize TP in such tumours. However, little is known of the factors that regulate the production or activity of these factors in the tumour microenvironment. As TNF-alpha has been shown to up-regulate TP expression in tumour cells in vitro we performed an immunohistochemical study to investigate the possibility that TNF-alpha may be involved in the regulation of TP expression by malignant breast epithelial cells in vivo. To do this, we used a cocktail of non-neutralizing monoclonal anti-TNF-alpha antibodies to visualize both TNF-alpha-expressing macrophages and TNF-alpha bound to its receptors on tumour cells and endothelial cells in a series of 93 invasive carcinomas of the breast. A semiquantitative grading system was then used to compare these staining patterns with that for TP in the same biopsies. TNF-alpha immunoreactivity was also compared with various important tumour variables known to relate to outcome in this disease (microvessel density, node status, grade, stage, receptor status and macrophage infiltration), as well as relapse-free and overall survival data for these patients. Our data show significant positive correlations between TNF-alpha bound to its receptors on tumour cells and: (1) TP protein production by tumour cells, and (2) axillary lymph

  11. Protective activity of butyrate on hydrogen peroxide-induced DNA damage in isolated human colonocytes and HT29 tumour cells.

    PubMed

    Rosignoli, P; Fabiani, R; De Bartolomeo, A; Spinozzi, F; Agea, E; Pelli, M A; Morozzi, G

    2001-10-01

    Epidemiological studies support the involvement of short-chain fatty acids (SCFA) in colon physiology and the protective role of butyrate on colon carcinogenesis. Among the possible mechanisms by which butyrate may exert its anti-carcinogenicity an antioxidant activity has been recently suggested. We investigated the effects of butyrate and mixtures of SCFA (butyrate, propionate and acetate) on DNA damage induced by H(2)O(2) in isolated human colonocytes and in two human colon tumour cell lines (HT29 and HT29 19A). Human colonocytes were isolated from endoscopically obtained samples and the DNA damage was assessed by the comet assay. H(2)O(2) induced DNA damage in normal colonocytes in a dose-dependent manner which was statistically significant at concentrations over 10 microM. At 15 microM H(2)O(2) DNA damage in HT29 and HT29 19A cells was significantly lower than that observed in normal colonocytes (P < 0.01). Pre-incubation of the cells with physiological concentrations of butyrate (6.25 and 12.5 mM) reduced H(2)O(2) (15 microM) induced damage by 33 and 51% in human colonocytes, 45 and 75% in HT29 and 30 and 80% in HT29 19A, respectively. Treatment of cells with a mixture of 25 mM acetate + 10.4 mM propionate + 6.25 mM butyrate did not induce DNA damage, while a mixture of 50 mM acetate + 20.8 mM propionate + 12.5 mM butyrate was weakly genotoxic only towards normal colonocytes. However, both mixtures were able to reduce the H(2)O(2)-induced DNA damage by about 50% in all cell types. The reported protective effect of butyrate might be important in pathogenetic mechanisms mediated by reactive oxygen species, and aids understanding of the apparent protection toward colorectal cancer exerted by dietary fibres, which enhance the butyrate bioavailability in the colonic mucosa. PMID:11577008

  12. Cytotoxic macrophage-released tumour necrosis factor-alpha (TNF-α) as a killing mechanism for cancer cell death after cold plasma activation

    NASA Astrophysics Data System (ADS)

    Kaushik, Nagendra Kumar; Kaushik, Neha; Min, Booki; Choi, Ki Hong; Hong, Young June; Miller, Vandana; Fridman, Alexander; Choi, Eun Ha

    2016-03-01

    The present study aims at studying the anticancer role of cold plasma-activated immune cells. The direct anti-cancer activity of plasma-activated immune cells against human solid cancers has not been described so far. Hence, we assessed the effect of plasma-treated RAW264.7 macrophages on cancer cell growth after co-culture. In particular, flow cytometer analysis revealed that plasma did not induce any cell death in RAW264.7 macrophages. Interestingly, immunofluorescence and western blot analysis confirmed that TNF-α released from plasma-activated macrophages acts as a tumour cell death inducer. In support of these findings, activated macrophages down-regulated the cell growth in solid cancer cell lines and induced cell death in vitro. Together our findings suggest plasma-induced reactive species recruit cytotoxic macrophages to release TNF-α, which blocks cancer cell growth and can have the potential to contribute to reducing tumour growth in vivo in the near future.

  13. Brain tumour cells interconnect to a functional and resistant network.

    PubMed

    Osswald, Matthias; Jung, Erik; Sahm, Felix; Solecki, Gergely; Venkataramani, Varun; Blaes, Jonas; Weil, Sophie; Horstmann, Heinz; Wiestler, Benedikt; Syed, Mustafa; Huang, Lulu; Ratliff, Miriam; Karimian Jazi, Kianush; Kurz, Felix T; Schmenger, Torsten; Lemke, Dieter; Gömmel, Miriam; Pauli, Martin; Liao, Yunxiang; Häring, Peter; Pusch, Stefan; Herl, Verena; Steinhäuser, Christian; Krunic, Damir; Jarahian, Mostafa; Miletic, Hrvoje; Berghoff, Anna S; Griesbeck, Oliver; Kalamakis, Georgios; Garaschuk, Olga; Preusser, Matthias; Weiss, Samuel; Liu, Haikun; Heiland, Sabine; Platten, Michael; Huber, Peter E; Kuner, Thomas; von Deimling, Andreas; Wick, Wolfgang; Winkler, Frank

    2015-12-01

    Astrocytic brain tumours, including glioblastomas, are incurable neoplasms characterized by diffusely infiltrative growth. Here we show that many tumour cells in astrocytomas extend ultra-long membrane protrusions, and use these distinct tumour microtubes as routes for brain invasion, proliferation, and to interconnect over long distances. The resulting network allows multicellular communication through microtube-associated gap junctions. When damage to the network occurred, tumour microtubes were used for repair. Moreover, the microtube-connected astrocytoma cells, but not those remaining unconnected throughout tumour progression, were protected from cell death inflicted by radiotherapy. The neuronal growth-associated protein 43 was important for microtube formation and function, and drove microtube-dependent tumour cell invasion, proliferation, interconnection, and radioresistance. Oligodendroglial brain tumours were deficient in this mechanism. In summary, astrocytomas can develop functional multicellular network structures. Disconnection of astrocytoma cells by targeting their tumour microtubes emerges as a new principle to reduce the treatment resistance of this disease. PMID:26536111

  14. Ion channels and transporters in tumour cell migration and invasion

    PubMed Central

    Schwab, Albrecht; Stock, Christian

    2014-01-01

    Cell migration is a central component of the metastatic cascade requiring a concerted action of ion channels and transporters (migration-associated transportome), cytoskeletal elements and signalling cascades. Ion transport proteins and aquaporins contribute to tumour cell migration and invasion among other things by inducing local volume changes and/or by modulating Ca2+ and H+ signalling. Targeting cell migration therapeutically bears great clinical potential, because it is a prerequisite for metastasis. Ion transport proteins appear to be attractive candidate target proteins for this purpose because they are easily accessible as membrane proteins and often overexpressed or activated in cancer. Importantly, a number of clinically widely used drugs are available whose anticipated efficacy as anti-tumour drugs, however, has now only begun to be evaluated. PMID:24493750

  15. High efficiency cell-specific targeting of cytokine activity

    NASA Astrophysics Data System (ADS)

    Garcin, Geneviève; Paul, Franciane; Staufenbiel, Markus; Bordat, Yann; van der Heyden, José; Wilmes, Stephan; Cartron, Guillaume; Apparailly, Florence; de Koker, Stefaan; Piehler, Jacob; Tavernier, Jan; Uzé, Gilles

    2014-01-01

    Systemic toxicity currently prevents exploiting the huge potential of many cytokines for medical applications. Here we present a novel strategy to engineer immunocytokines with very high targeting efficacies. The method lies in the use of mutants of toxic cytokines that markedly reduce their receptor-binding affinities, and that are thus rendered essentially inactive. Upon fusion to nanobodies specifically binding to marker proteins, activity of these cytokines is selectively restored for cell populations expressing this marker. This ‘activity-by-targeting’ concept was validated for type I interferons and leptin. In the case of interferon, activity can be directed to target cells in vitro and to selected cell populations in mice, with up to 1,000-fold increased specific activity. This targeting strategy holds promise to revitalize the clinical potential of many cytokines.

  16. Differentiation of tumour-promoting stromal myofibroblasts by cancer exosomes.

    PubMed

    Webber, J P; Spary, L K; Sanders, A J; Chowdhury, R; Jiang, W G; Steadman, R; Wymant, J; Jones, A T; Kynaston, H; Mason, M D; Tabi, Z; Clayton, A

    2015-01-15

    Activation of myofibroblast rich stroma is a rate-limiting step essential for cancer progression. The responsible factors are not fully understood, but TGFβ1 is probably critical. A proportion of TGFβ1 is associated with extracellular nano-vesicles termed exosomes, secreted by carcinoma cells, and the relative importance of soluble and vesicular TGFβ in stromal activation is presented. Prostate cancer exosomes triggered TGFβ1-dependent fibroblast differentiation, to a distinctive myofibroblast phenotype resembling stromal cells isolated from cancerous prostate tissue; supporting angiogenesis in vitro and accelerating tumour growth in vivo. Myofibroblasts generated using soluble TGFβ1 were not pro-angiogenic or tumour-promoting. Cleaving heparan sulphate side chains from the exosome surface had no impact on TGFβ levels yet attenuated SMAD-dependent signalling and myofibroblastic differentiation. Eliminating exosomes from the cancer cell secretome, targeting Rab27a, abolished differentiation and lead to failure in stroma-assisted tumour growth in vivo. Exosomal TGFβ1 is therefore required for the formation of tumour-promoting stroma. PMID:24441045

  17. Electrochemotherapy on liver tumours in rabbits.

    PubMed Central

    Ramirez, L. H.; Orlowski, S.; An, D.; Bindoula, G.; Dzodic, R.; Ardouin, P.; Bognel, C.; Belehradek, J.; Munck, J. N.; Mir, L. M.

    1998-01-01

    Electrochemotherapy (ECT) is a new therapeutic approach combining the effects of a low-permeant cytotoxic drug, bleomycin (BLM), administered i.v. and cell-permeabilizing electric pulses (EPs) locally delivered to tumours. The transient permeabilization of the cell membrane by the EPs allows free access of BLM to its intracellular targets, largely enhancing BLM's cytotoxic effects. ECT efficacy has been proved so far on transplanted subcutaneous murine tumours and on subcutaneous metastases in humans. Here, we present the first study of the effects of ECT on tumours transplanted to livers in rabbits. We used a recently developed EP applicator consisting of an array of parallel and equidistant needles to be inserted in tissues. Effects of EPs alone or of ECT were assessed by histological analysis, tumour growth rates and survival of the treated animals. A transient blood hypoperfusion was seen in the electropulsed areas, with or without BLM, related to EP-dependent vasoconstriction but this had no major effects on cell survival. Long-term effects depended on the presence of BLM at the time of EP delivery. Almost complete tumour necrosis was observed after ECT, resulting from both BLM direct cytotoxic effects on electropermeabilized tumour cells and indirect effects on the tumour vessels. A large reduction in tumour growth rate and significantly longer survival times were scored in comparison with control rabbits. Moreover, ECT of liver tumours was well tolerated and devoid of systemic side-effects. When ECT was associated with a local interleukin 2-based immunotherapy, increased local anti-tumour effectiveness as well as a large decrease in the number of metastases were observed. Thus, ECT could become a novel treatment modality for liver tumours and other solid internal malignancies. Images Figure 1 Figure 2 PMID:9649121

  18. An active target for the accelerator-based transmutation system

    SciTech Connect

    Grebyonkin, K. F.

    1995-09-15

    Consideration is given to the possibility of radical reduction in power requirements to the proton accelerator of the electronuclear reactor due to neutron multiplication both in the blanket and the target of an active material. The target is supposed to have the fast-neutron spectrum, and the blanket--the thermal one. The blanket and the target are separated by the thermal neutrons absorber, which is responsible for the neutron decoupling of the active target and blanket. Also made are preliminary estimations which illustrate that the realization of the idea under consideration can lead to significant reduction in power requirements to the proton beam and, hence considerably improve economic characteristics of the electronuclear reactor.

  19. Photodynamic therapy augments the efficacy of oncolytic vaccinia virus against primary and metastatic tumours in mice

    PubMed Central

    Gil, M; Bieniasz, M; Seshadri, M; Fisher, D; Ciesielski, M J; Chen, Y; Pandey, R K; Kozbor, D

    2011-01-01

    Background: Therapies targeted towards the tumour vasculature can be exploited for the purpose of improving the systemic delivery of oncolytic viruses to tumours. Photodynamic therapy (PDT) is a clinically approved treatment for cancer that is known to induce potent effects on tumour vasculature. In this study, we examined the activity of PDT in combination with oncolytic vaccinia virus (OVV) against primary and metastatic tumours in mice. Methods: The effect of 2-[1-hexyloxyethyl-]-2-devinyl pyropheophorbide-a (HPPH)-sensitised-PDT on the efficacy of oncolytic virotherapy was investigated against subcutaneously implanted syngeneic murine NXS2 neuroblastoma and human FaDu head and neck squamous cell carcinoma xenografts in nude mice. Treatment efficacy was evaluated by monitoring tumour growth and survival. The effects of combination treatment on vascular function were examined using magnetic resonance imaging (MRI) and immunohistochemistry, whereas viral replication in tumour cells was analysed by a standard plaque assay. Normal tissue phototoxicity following PDT-OV treatment was studied using the mouse foot response assay. Results: Combination of PDT with OVV resulted in inhibition of primary and metastatic tumour growth compared with either monotherapy. PDT-induced vascular disruption resulted in higher intratumoural viral titres compared with the untreated tumours. Five days after delivery of OVV, there was a loss of blood flow to the interior of tumour that was associated with infiltration of neutrophils. Administration of OVV did not result in any additional photodynamic damage to normal mouse foot tissue. Conclusion: These results provide evidence into the usefulness of PDT as a means of enhancing intratumoural replication and therapeutic efficacy of OV. PMID:21989183

  20. DNA replication stress in CHK1-depleted tumour cells triggers premature (S-phase) mitosis through inappropriate activation of Aurora kinase B

    PubMed Central

    Zuazua-Villar, P; Rodriguez, R; Gagou, M E; Eyers, P A; Meuth, M

    2014-01-01

    The disruption of DNA replication in cells triggers checkpoint responses that slow-down S-phase progression and protect replication fork integrity. These checkpoints are also determinants of cell fate and can help maintain cell viability or trigger cell death pathways. CHK1 has a pivotal role in such S-phase responses. It helps maintain fork integrity during replication stress and protects cells from several catastrophic fates including premature mitosis, premature chromosome condensation and apoptosis. Here we investigated the role of CHK1 in protecting cancer cells from premature mitosis and apoptosis. We show that premature mitosis (characterized by the induction of histone H3 phosphorylation, aberrant chromatin condensation, and persistent RPA foci in arrested S-phase cells) is induced in p53-deficient tumour cells depleted of CHK1 when DNA synthesis is disrupted. These events are accompanied by an activation of Aurora kinase B in S-phase cells that is essential for histone H3 Ser10 phosphorylation. Histone H3 phosphorylation precedes the induction of apoptosis in p53−/− tumour cell lines but does not appear to be required for this fate as an Aurora kinase inhibitor suppresses phosphorylation of both Aurora B and histone H3 but has little effect on cell death. In contrast, only a small fraction of p53+/+ tumour cells shows this premature mitotic response, although they undergo a more rapid and robust apoptotic response. Taken together, our results suggest a novel role for CHK1 in the control of Aurora B activation during DNA replication stress and support the idea that premature mitosis is a distinct cell fate triggered by the disruption of DNA replication when CHK1 function is suppressed. PMID:24853431

  1. Oncoprotein stability after tumour resection.

    PubMed Central

    Ong, G.; Gullick, W.; Sikora, K.

    1990-01-01

    The means by which oncogenes and their products activate malignant transformation are currently under intense investigation. However, published papers on experiments using human tumour material do not always report in detail their methods of collection or storage of the specimens. In order to assess the stability of oncogene encoded proteins following collection or storage of human tumour biopsies, we have examined the rate of decay of the c-myc, neu and EGF-receptor proteins. Solid tumours, containing amplified copies of each oncogene, were established in nude mice and the stability of the oncogene protein in portions of each tumour, left in phosphate buffered saline at room temperature for varying time intervals, was examined by immunoblotting. Intact EGF-receptor and neu oncoproteins were present even after 24 h under these conditions while the c-myc protein was apparently rapidly degraded after 20 min. These data demonstrate that oncogene products decay at different rates after tumour resection and that collection of human biopsies should take this into account in order to provide the basis for consistent measurements of protein expression. Images Figure 1 Figure 2 Figure 3 PMID:2139576

  2. Loss of PHD3 allows tumours to overcome hypoxic growth inhibition and sustain proliferation through EGFR

    PubMed Central

    Henze, Anne-Theres; Garvalov, Boyan K.; Seidel, Sascha; Cuesta, Angel M.; Ritter, Mathias; Filatova, Alina; Foss, Franziska; Dopeso, Higinio; Essmann, Clara L.; Maxwell, Patrick H.; Reifenberger, Guido; Carmeliet, Peter; Acker-Palmer, Amparo; Acker, Till

    2014-01-01

    Solid tumours are exposed to microenvironmental factors such as hypoxia that normally inhibit cell growth. However, tumour cells are capable of counteracting these signals through mechanisms that are largely unknown. Here we show that the prolyl hydroxylase PHD3 restrains tumour growth in response to microenvironmental cues through the control of EGFR. PHD3 silencing in human gliomas or genetic deletion in a murine high-grade astrocytoma model markedly promotes tumour growth and the ability of tumours to continue growing under unfavourable conditions. The growth-suppressive function of PHD3 is independent of the established PHD3 targets HIF and NF-κB and its hydroxylase activity. Instead, loss of PHD3 results in hyperphosphorylation of epidermal growth factor receptor (EGFR). Importantly, epigenetic/genetic silencing of PHD3 preferentially occurs in gliomas without EGFR amplification. Our findings reveal that PHD3 inactivation provides an alternative route of EGFR activation through which tumour cells sustain proliferative signalling even under conditions of limited oxygen availability. PMID:25420773

  3. Long Term Effect of Curcumin in Restoration of Tumour Suppressor p53 and Phase-II Antioxidant Enzymes via Activation of Nrf2 Signalling and Modulation of Inflammation in Prevention of Cancer

    PubMed Central

    Das, Laxmidhar; Vinayak, Manjula

    2015-01-01

    Inhibition of carcinogenesis may be a consequence of attenuation of oxidative stress via activation of antioxidant defence system, restoration and stabilization of tumour suppressor proteins along with modulation of inflammatory mediators. Previously we have delineated significant role of curcumin during its long term effect in regulation of glycolytic pathway and angiogenesis, which in turn results in prevention of cancer via modulation of stress activated genes. Present study was designed to investigate long term effect of curcumin in regulation of Nrf2 mediated phase-II antioxidant enzymes, tumour suppressor p53 and inflammation under oxidative tumour microenvironment in liver of T-cell lymphoma bearing mice. Inhibition of Nrf2 signalling observed during lymphoma progression, resulted in down regulation of phase II antioxidant enzymes, p53 as well as activation of inflammatory signals. Curcumin potentiated significant increase in Nrf2 activation. It restored activity of phase-II antioxidant enzymes like GST, GR, NQO1, and tumour suppressor p53 level. In addition, curcumin modulated inflammation via upregulation of TGF-β and reciprocal regulation of iNOS and COX2. The study suggests that during long term effect, curcumin leads to prevention of cancer by inducing phase-II antioxidant enzymes via activation of Nrf2 signalling, restoration of tumour suppressor p53 and modulation of inflammatory mediators like iNOS and COX2 in liver of lymphoma bearing mice. PMID:25860911

  4. Brain and spinal tumour.

    PubMed

    Goh, C H; Lu, Y Y; Lau, B L; Oy, J; Lee, H K; Liew, D; Wong, A

    2014-12-01

    This study reviewed the epidemiology of brain and spinal tumours in Sarawak from January 2009 till December 2012. The crude incidence of brain tumour in Sarawak was 4.6 per 100,000 population/year with cumulative rate 0.5%. Meningioma was the most common brain tumour (32.3%) and followed by astrocytoma (19.4%). Only brain metastases showed a rising trend and cases were doubled in 4 years. This accounted for 15.4% and lung carcinoma was the commonest primary. Others tumour load were consistent. Primitive neuroectodermal tumour (PNET) and astrocytoma were common in paediatrics (60%). We encountered more primary spinal tumour rather than spinal metastases. Intradural schwannoma was the commonest and frequently located at thoracic level. The current healthcare system in Sarawak enables a more consolidate data collection to reflect accurate brain tumours incidence. This advantage allows subsequent future survival outcome research and benchmarking for healthcare resource planning. PMID:25934956

  5. IgA EGFR antibodies mediate tumour killing in vivo

    PubMed Central

    Boross, Peter; Lohse, Stefan; Nederend, Maaike; Jansen, Johannes Hendrik Marco; van Tetering, Geert; Dechant, Michael; Peipp, Matthias; Royle, Louise; Liew, Li Phing; Boon, Louis; van Rooijen, Nico; Bleeker, Wim K; Parren, Paul W H I; van de Winkel, Jan G J; Valerius, Thomas; Leusen, Jeanette H W

    2013-01-01

    Currently all approved anti-cancer therapeutic monoclonal antibodies (mAbs) are of the IgG isotype, which rely on Fcgamma receptors (FcγRs) to recruit cellular effector functions. In vitro studies showed that targeting of FcαRI (CD89) by bispecific antibodies (bsAbs) or recombinant IgA resulted in more effective elimination of tumour cells by myeloid effector cells than targeting of FcγR. Here we studied the in vivo anti-tumour activity of IgA EGFR antibodies generated using the variable sequences of the chimeric EGFR antibody cetuximab. Using FcαRI transgenic mice, we demonstrated significant in vivo anti-tumour activity of IgA2 EGFR against A431 cells in peritoneal and lung xenograft models, as well as against B16F10-EGFR cells in a lung metastasis model in immunocompetent mice. IgA2 EGFR was more effective than cetuximab in a short-term syngeneic peritoneal model using EGFR-transfected Ba/F3 target cells. The in vivo cytotoxic activity of IgA2 EGFR was mediated by macrophages and was significantly decreased in the absence of FcαRI. These results support the potential of targeting FcαRI for effective antibody therapy of cancer. The study reveals that IgA antibodies directed against EGFR and engaging Fcalpha receptor (FcαRI) on effector cells, have in vivo anti-cancer activity. These data support the development of novel immunotherapeutic strategies based on targeting FcαRI. PMID:23918228

  6. Mipsagargin, a novel thapsigargin-based PSMA-activated prodrug: results of a first-in-man phase I clinical trial in patients with refractory, advanced or metastatic solid tumours

    PubMed Central

    Mahalingam, D; Wilding, G; Denmeade, S; Sarantopoulas, J; Cosgrove, D; Cetnar, J; Azad, N; Bruce, J; Kurman, M; Allgood, V E; Carducci, M

    2016-01-01

    Background: Mipsagargin (G-202; (8-O-(12-aminododecanoyl)-8-O-debutanoyl thapsigargin)-Asp-γ-Glu-γ-Glu-γ-GluGluOH)) is a novel thapsigargin-based targeted prodrug that is activated by PSMA-mediated cleavage of an inert masking peptide. The active moiety is an inhibitor of the sarcoplasmic/endoplasmic reticulum calcium adenosine triphosphatase (SERCA) pump protein that is necessary for cellular viability. We evaluated the safety of mipsagargin in patients with advanced solid tumours and established a recommended phase II dosing (RP2D) regimen. Methods: Patients with advanced solid tumours received mipsagargin by intravenous infusion on days 1, 2 and 3 of 28-day cycles and were allowed to continue participation in the absence of disease progression or unacceptable toxicity. The dosing began at 1.2 mg m−2 and was escalated using a modified Fibonacci schema to determine maximally tolerated dose (MTD) with an expansion cohort at the RP2D. Plasma was analysed for mipsagargin pharmacokinetics and response was assessed using RECIST criteria. Results: A total of 44 patients were treated at doses ranging from 1.2 to 88 mg m−2, including 28 patients in the dose escalation phase and 16 patients in an expansion cohort. One dose-limiting toxicity (DLT; Grade 3 rash) was observed in the dose escalation portion of the study. At 88 mg m−2, observations of Grade 2 infusion-related reaction (IRR, 2 patients) and Grade 2 creatinine elevation (1 patient) led to declaration of 66.8 mg m−2 as the recommended phase II dose (RP2D). Across the study, the most common treatment-related adverse events (AEs) were fatigue, rash, nausea, pyrexia and IRR. Two patients developed treatment-related Grade 3 acute renal failure that was reversible during the treatment-free portion of the cycle. To help ameliorate the IRR and creatinine elevations, a RP2D of 40 mg m−2 on day 1 and 66.8 mg m−2 on days 2 and 3 with prophylactic premedications and hydration on each

  7. Lymphovascular and neural regulation of metastasis: Shared tumour signalling pathways and novel therapeutic approaches

    PubMed Central

    Le, C.P.; Karnezis, T.; Achen, M. G.; Stacker, S.A.; Sloan, E.K.

    2014-01-01

    The progression of cancer is supported by a wide variety of non-neoplastic cell types which make up the tumour stroma, including immune cells, endothelial cells, cancer-associated fibroblasts and nerve fibres. These host cells contribute molecular signals that enhance primary tumour growth and provide physical avenues for metastatic dissemination. This article provides an overview of the role of blood vessels, lymphatic vessels and nerve fibres in the tumour microenvironment, and highlights the interconnected molecular signalling pathways that control their development and activation in cancer. Further the review highlights the known pharmacological agents which target these pathways and discusses the potential therapeutic uses of drugs that target angiogenesis, lymphangiogenesis and stress response pathways in the different stages of cancer care. PMID:24267548

  8. A helium gas scintillator active target for photoreaction measurements

    NASA Astrophysics Data System (ADS)

    Al Jebali, Ramsey; Annand, John R. M.; Adler, Jan-Olof; Akkurt, Iskender; Buchanan, Emma; Brudvik, Jason; Fissum, Kevin; Gardner, Simon; Hamilton, David J.; Hansen, Kurt; Isaksson, Lennart; Livingston, Kenneth; Lundin, Magnus; McGeorge, John C.; MacGregor, Ian J. D.; MacRae, Roderick; Middleton, Duncan G.; Reiter, Andreas J. H.; Rosner, Günther; Schröder, Bent; Sjögren, Johan; Sokhan, Daria; Strandberg, Bruno

    2015-10-01

    A multi-cell He gas scintillator active target, designed for the measurement of photoreaction cross sections, is described. The target has four main chambers, giving an overall thickness of 0.103 g/cm3 at an operating pressure of 2 MPa. Scintillations are read out by photomultiplier tubes and the addition of small amounts of N2 to the He, to shift the scintillation emission from UV to visible, is discussed. First results of measurements at the MAX IV Laboratory tagged-photon facility show that the target has a timing resolution of around 1 ns and can cope well with a high-flux photon beam. The determination of reaction cross sections from target yields relies on a Monte Carlo simulation, which considers scintillation light transport, photodisintegration processes in 4He, background photon interactions in target windows and interactions of the reaction-product particles in the gas and target container. The predictions of this simulation are compared to the measured target response.

  9. Multiple mechanisms of MYCN dysregulation in Wilms tumour.

    PubMed

    Williams, Richard D; Chagtai, Tasnim; Alcaide-German, Marisa; Apps, John; Wegert, Jenny; Popov, Sergey; Vujanic, Gordan; van Tinteren, Harm; van den Heuvel-Eibrink, Marry M; Kool, Marcel; de Kraker, Jan; Gisselsson, David; Graf, Norbert; Gessler, Manfred; Pritchard-Jones, Kathy

    2015-03-30

    Genomic gain of the proto-oncogene transcription factor gene MYCN is associated with poor prognosis in several childhood cancers. Here we present a comprehensive copy number analysis of MYCN in Wilms tumour (WT), demonstrating that gain of this gene is associated with anaplasia and with poorer relapse-free and overall survival, independent of histology. Using whole exome and gene-specific sequencing, together with methylation and expression profiling, we show that MYCN is targeted by other mechanisms, including a recurrent somatic mutation, P44L, and specific DNA hypomethylation events associated with MYCN overexpression in tumours with high risk histologies. We describe parallel evolution of genomic copy number gain and point mutation of MYCN in the contralateral tumours of a remarkable bilateral case in which independent contralateral mutations of TP53 also evolve over time. We report a second bilateral case in which MYCN gain is a germline aberration. Our results suggest a significant role for MYCN dysregulation in the molecular biology of Wilms tumour. We conclude that MYCN gain is prognostically significant, and suggest that the novel P44L somatic variant is likely to be an activating mutation. PMID:25749049

  10. Multiple mechanisms of MYCN dysregulation in Wilms tumour

    PubMed Central

    Williams, Richard D.; Chagtai, Tasnim; Alcaide-German, Marisa; Apps, John; Wegert, Jenny; Popov, Sergey; Vujanic, Gordan; van Tinteren, Harm; van den Heuvel-Eibrink, Marry M.; Kool, Marcel; de Kraker, Jan; Gisselsson, David; Graf, Norbert; Gessler, Manfred; Pritchard-Jones, Kathy

    2015-01-01

    Genomic gain of the proto-oncogene transcription factor gene MYCN is associated with poor prognosis in several childhood cancers. Here we present a comprehensive copy number analysis of MYCN in Wilms tumour (WT), demonstrating that gain of this gene is associated with anaplasia and with poorer relapse-free and overall survival, independent of histology. Using whole exome and gene-specific sequencing, together with methylation and expression profiling, we show that MYCN is targeted by other mechanisms, including a recurrent somatic mutation, P44L, and specific DNA hypomethylation events associated with MYCN overexpression in tumours with high risk histologies. We describe parallel evolution of genomic copy number gain and point mutation of MYCN in the contralateral tumours of a remarkable bilateral case in which independent contralateral mutations of TP53 also evolve over time. We report a second bilateral case in which MYCN gain is a germline aberration. Our results suggest a significant role for MYCN dysregulation in the molecular biology of Wilms tumour. We conclude that MYCN gain is prognostically significant, and suggest that the novel P44L somatic variant is likely to be an activating mutation. PMID:25749049

  11. Anti-tumour and anti-metastatic activity of 3-(P-Chlorophenyl)-2,3-Dihydro-3-Hydroxythiazolo (3,2-A)-Benzimidazole-2-acetic acid (WY-13,876).

    PubMed Central

    Fenichel, R. L.; Gregory, F. J.; Alburn, H. E.

    1976-01-01

    Extensive investigation of 3-(p-chlorophenyl)-2,3-dihydro-3-hydroxythiazolo(3,2-alpha)-benzimidazole-2-acetic acid (Wy-13,876) in BDF1 mice implanted with Lewis lung tumour has shown that it is an effective anti-tumour and anti-metastatic agent. In vitro examination using HEp-2 human epidermal tumour cells has indicated that Wy-13,876 is not cytotoxic. When mice implanted with Lewis lung tumour and treated with Wy-13,876 are also injected with anti-thymocyte serum, an increase in lung metastases is observed suggesting that thymocyte activity is involved in the drug's mechanism of action. An increase in peripheral T lymphocytes observed in rats 18 h after a single oral dose of Wy-13,876 further supports this possibility. When Wy-13,876 is given to tumour -bearing mice in combination with low, ineffective doses of 5-fluorouracil or cyclophosphamide, further reduction of primary tumour growth is observed. PMID:1083737

  12. Active Targeted Drug Delivery for Microbes Using Nano-Carriers

    PubMed Central

    Lin, Yung-Sheng; Lee, Ming-Yuan; Yang, Chih-Hui; Huang, Keng-Shiang

    2015-01-01

    Although vaccines and antibiotics could kill or inhibit microbes, many infectious diseases remain difficult to treat because of acquired resistance and adverse side effects. Nano-carriers-based technology has made significant progress for a long time and is introducing a new paradigm in drug delivery. However, it still has some challenges like lack of specificity toward targeting the infectious site. Nano-carriers utilized targeting ligands on their surface called ‘active target’ provide the promising way to solve the problems like accelerating drug delivery to infectious areas and preventing toxicity or side-effects. In this mini review, we demonstrate the recent studies using the active targeted strategy to kill or inhibit microbes. The four common nano-carriers (e.g. liposomes, nanoparticles, dendrimers and carbon nanotubes) delivering encapsulated drugs are introduced. PMID:25877093

  13. Acoustic gaze adjustments during active target selection in echolocating porpoises.

    PubMed

    Wisniewska, Danuta Maria; Johnson, Mark; Beedholm, Kristian; Wahlberg, Magnus; Madsen, Peter Teglberg

    2012-12-15

    Visually dominant animals use gaze adjustments to organize perceptual inputs for cognitive processing. Thereby they manage the massive sensory load from complex and noisy scenes. Echolocation, as an active sensory system, may provide more opportunities to control such information flow by adjusting the properties of the sound source. However, most studies of toothed whale echolocation have involved stationed animals in static auditory scenes for which dynamic information control is unnecessary. To mimic conditions in the wild, we designed an experiment with captive, free-swimming harbor porpoises tasked with discriminating between two hydrophone-equipped targets and closing in on the selected target; this allowed us to gain insight into how porpoises adjust their acoustic gaze in a multi-target dynamic scene. By means of synchronized cameras, an acoustic tag and on-target hydrophone recordings we demonstrate that porpoises employ both beam direction control and range-dependent changes in output levels and pulse intervals to accommodate their changing spatial relationship with objects of immediate interest. We further show that, when switching attention to another target, porpoises can set their depth of gaze accurately for the new target location. In combination, these observations imply that porpoises exert precise vocal-motor control that is tied to spatial perception akin to visual accommodation. Finally, we demonstrate that at short target ranges porpoises narrow their depth of gaze dramatically by adjusting their output so as to focus on a single target. This suggests that echolocating porpoises switch from a deliberative mode of sensorimotor operation to a reactive mode when they are close to a target. PMID:23175527

  14. Effect of target probability on pre-stimulus brain activity.

    PubMed

    Lucci, G; Berchicci, M; Perri, R L; Spinelli, D; Di Russo, F

    2016-05-13

    Studies on perceptual decision-making showed that manipulating the proportion of target and non-target stimuli affects the behavioral performance. Tasks with high frequency of targets are associated to faster response times (RTs) conjunctively to higher number of errors (reflecting a response bias characterized by speed/accuracy trade-off) when compared to conditions with low frequency of targets. Electroencephalographic studies well described modulations of post-stimulus event-related potentials as effect of the stimulus probability; in contrast, in the present study we focused on the pre-stimulus preparatory activities subtending the response bias. Two versions of a Go/No-go task characterized by different proportion of Go stimuli (88% vs. 12%) were adopted. In the task with frequent go trials, we observed a strong enhancement in the motor preparation as indexed by the Bereitschaftspotential (BP, previously associated with activity within the supplementary motor area), faster RTs, and larger commission error rate than in the task with rare go trials. Contemporarily with the BP, a right lateralized prefrontal negativity (lateral pN, previously associated with activity within the dorsolateral prefrontal cortex) was larger in the task with rare go trial. In the post-stimulus processing stage, we confirmed that the N2 and the P3 components were larger for rare trials, irrespective of the Go/No-go stimulus category. The increase of activities recorded in the preparatory phase related to frequency of targets is consistent with the view proposed in accumulation models of perceptual decision for which target frequency affects the subjective baseline, reducing the distance between the starting-point and the response boundary, which determines the response speed. PMID:26912279

  15. Eliciting Production of L2 Target Structures through Priming Activities

    ERIC Educational Resources Information Center

    McDonough, Kim; Trofimovich, Pavel; Neumann, Heike

    2015-01-01

    This study focuses on the pedagogical applications of structural priming research in an English for academic purposes (EAP) context, investigating whether priming activities are an effective tool for eliciting production of target grammatical structures. University students across four EAP classes carried out a total of 6 information-exchange…

  16. Sertoliform cystadenoma: a rare benign tumour of the rete testis

    PubMed Central

    2013-01-01

    Abstract Sertoliform cystadenoma of the rete testis represents an uncommon benign tumour. They appear in patients from 26 to 62 years of age. We describe a case of a 66-year-old man with a tumour in the area of the epididymal head. The tumour markers were not increased. Under the assumption of a malignant testicular tumour an inguinal orchiectomy was performed. The cut surface of this tumour was of grey/white color and showed small cysts. The tumour consisted of two compartments. The epithelial like tumour cells showed a sertoliform growth pattern and cystic dilatations. In between the tumour cells repeatedly actin expressing sclerotic areas could be recognized as the second tumour component. Proliferative activity was not increased. Immunohistochemically the tumour cells were positiv for inhibin, S-100, and CD 99. Alpha feto protein (AFP), human chorionic gonadotropin (ß-HCG) and placental alkaline phosphatase (PLAP) as well as synaptophysin, epithelial membrane antigene (EMA), and BCL-2 were not expressed. As far as we know this is the sixth reported case of this tumour. Because of the benign nature of this tumour the correct diagnosis is important for the intra- and postoperative management. Here we present a case of this rare tumour and discuss potential differential diagnosis. Virtual Slides The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1956026143857335 PMID:23406299

  17. The unfolded protein response selectively targets active smoothened mutants.

    PubMed

    Marada, Suresh; Stewart, Daniel P; Bodeen, William J; Han, Young-Goo; Ogden, Stacey K

    2013-06-01

    The Hedgehog signaling pathway, an essential regulator of developmental patterning, has been implicated in playing causative and survival roles in a range of human cancers. The signal-transducing component of the pathway, Smoothened, has revealed itself to be an efficacious therapeutic target in combating oncogenic signaling. However, therapeutic challenges remain in cases where tumors acquire resistance to Smoothened antagonists, and also in cases where signaling is driven by active Smoothened mutants that exhibit reduced sensitivity to these compounds. We previously demonstrated that active Smoothened mutants are subjected to prolonged endoplasmic reticulum (ER) retention, likely due to their mutations triggering conformation shifts that are detected by ER quality control. We attempted to exploit this biology and demonstrate that deregulated Hedgehog signaling driven by active Smoothened mutants is specifically attenuated by ER stressors that induce the unfolded protein response (UPR). Upon UPR induction, active Smoothened mutants are targeted by ER-associated degradation, resulting in attenuation of inappropriate pathway activity. Accordingly, we found that the UPR agonist thapsigargin attenuated mutant Smoothened-induced phenotypes in vivo in Drosophila melanogaster. Wild-type Smoothened and physiological Hedgehog patterning were not affected, suggesting that UPR modulation may provide a novel therapeutic window to be evaluated for targeting active Smoothened mutants in disease. PMID:23572559

  18. Inhibition of P-glycoprotein function by XR9576 in a solid tumour model can restore anticancer drug efficacy.

    PubMed

    Walker, J; Martin, C; Callaghan, R

    2004-03-01

    Resistance to cancer chemotherapy involves both altered drug activity at the designated target and modified intra-tumour pharmacokinetic properties (e.g. uptake, metabolism). The membrane transporter P-glycoprotein (P-gp) plays a major role in pharmacokinetic resistance by preventing sufficient intracellular accumulation of several anticancer agents. Whilst inhibiting P-gp has great potential to restore chemotherapeutic effectiveness in blood-borne cancers, the situation in solid tumours is less clear. Therefore, the degree of resistance tumours pose to the cytotoxicity of vinblastine and doxorubicin was characterised using the multicellular tumour spheroid model. Tumour spheroids were generated from either drug-sensitive MCF7(WT) breast cancer cells or a resistant P-gp-expressing variant (NCI/ADR(Res)). Drug-induced cytotoxicity in tumour spheroids was measured using an outgrowth assay and compared with that observed in monolayer cultures. As anticipated, the 3-D organisation of MCF7(WT) in tumour spheroids was associated with a reduction in the potency of doxorubicin and vinblastine-i.e. the inherent multicellular resistance phenomenon. In contrast, tumour spheroids from NCI/ADR(Res) cells did not display multicellular resistance. However their constitutive expression of P-gp reduced the potency of both anticancer drugs. Moreover, the highly potent P-gp inhibitor, the anthranilic acid derivative, XR9576, was able to restore the cytotoxic efficacy of both drugs in tumour spheroids comprising NCI/ADR(Res) cells. The results suggest that inhibition of P-gp in solid tumours is achievable and that generation of potent inhibitors will provide a significant benefit towards restoration of chemotherapy in solid tissues. PMID:14962729

  19. Angiotensin inhibition enhances drug delivery and potentiates chemotherapy by decompressing tumour blood vessels

    PubMed Central

    Chauhan, Vikash P.; Martin, John D.; Liu, Hao; Lacorre, Delphine A.; Jain, Saloni R.; Kozin, Sergey V.; Stylianopoulos, Triantafyllos; Mousa, Ahmed S.; Han, Xiaoxing; Adstamongkonkul, Pichet; Popović, Zoran; Huang, Peigen; Bawendi, Moungi G.; Boucher, Yves; Jain, Rakesh K.

    2013-01-01

    Cancer and stromal cells actively exert physical forces (solid stress) to compress tumour blood vessels, thus reducing vascular perfusion. Tumour interstitial matrix also contributes to solid stress, with hyaluronan implicated as the primary matrix molecule responsible for vessel compression because of its swelling behaviour. Here we show, unexpectedly, that hyaluronan compresses vessels only in collagen-rich tumours, suggesting that collagen and hyaluronan together are critical targets for decompressing tumour vessels. We demonstrate that the angiotensin inhibitor losartan reduces stromal collagen and hyaluronan production, associated with decreased expression of profibrotic signals TGF-β1, CCN2 and ET-1, downstream of angiotensin-II-receptor-1 inhibition. Consequently, losartan reduces solid stress in tumours resulting in increased vascular perfusion. Through this physical mechanism, losartan improves drug and oxygen delivery to tumours, thereby potentiating chemotherapy and reducing hypoxia in breast and pancreatic cancer models. Thus, angiotensin inhibitors —inexpensive drugs with decades of safe use — could be rapidly repurposed as cancer therapeutics. PMID:24084631

  20. Update on HER-2 as a target for cancer therapy: HER2/neu peptides as tumour vaccines for T cell recognition

    PubMed Central

    Correa, Isabel; Plunkett, Tim

    2001-01-01

    During the past decade there has been renewed interest in the use of vaccine immunotherapy for the treatment of cancer. This review focuses on HER2/neu, a tumour-associated antigen that is overexpressed in 10–40% of breast cancers and other carcinomata. Several immunogenic HER2/neu peptides recognized by T lymphocytes have been identified to be included in cancer vaccines. Some of these peptides have been assessed in clinical trials of patients with breast and ovarian cancer. Although it has been possible to detect immunological responses against the peptides in the immunized patients, no clinical responses have so far been described. Immunological tolerance to self-antigens like HER2/neu may limit the functional immune responses against them. It will be of interest to determine whether immune responses against HER2/neu epitopes can be of relevance to cancer treatment. PMID:11737893

  1. FDG uptake, a surrogate of tumour hypoxia?

    PubMed Central

    Van de Wiele, Christophe

    2008-01-01

    Introduction Tumour hyperglycolysis is driven by activation of hypoxia-inducible factor-1 (HIF-1) through tumour hypoxia. Accordingly, the degree of 2-fluro-2-deoxy-d-glucose (FDG) uptake by tumours might indirectly reflect the level of hypoxia, obviating the need for more specific radiopharmaceuticals for hypoxia imaging. Discussion In this paper, available data on the relationship between hypoxia and FDG uptake by tumour tissue in vitro and in vivo are reviewed. In pre-clinical in vitro studies, acute hypoxia was consistently shown to increase FDG uptake by normal and tumour cells within a couple of hours after onset with mobilisation or modification of glucose transporters optimising glucose uptake, followed by a delayed response with increased rates of transcription of GLUT mRNA. In pre-clinical imaging studies on chronic hypoxia that compared FDG uptake by tumours grown in rat or mice to uptake by FMISO, the pattern of normoxic and hypoxic regions within the human tumour xenografts, as imaged by FMISO, largely correlated with glucose metabolism although minor locoregional differences could not be excluded. In the clinical setting, data are limited and discordant. Conclusion Further evaluation of FDG uptake by various tumour types in relation to intrinsic and bioreductive markers of hypoxia and response to radiotherapy or hypoxia-dependent drugs is needed to fully assess its application as a marker of hypoxia in the clinical setting. PMID:18509637

  2. Active helium target: Neutron scalar polarizability extraction via Compton scattering

    SciTech Connect

    Morris, Meg Hornidge, David; Annand, John; Strandberg, Bruno

    2015-12-31

    Precise measurement of the neutron scalar polarizabilities has been a lasting challenge because of the lack of a free-neutron target. Led by the University of Glasgow and the Mount Allison University groups of the A2 collaboration in Mainz, Germany, preparations have begun to test a recent theoretical model with an active helium target with the hope of determining these elusive quantities with small statistical, systematic, and model-dependent errors. Apparatus testing and background-event simulations have been carried out, with the full experiment projected to run in 2015. Once determined, these values can be applied to help understand quantum chromodynamics in the nonperturbative region.

  3. Active helium target: Neutron scalar polarizability extraction via Compton scattering

    NASA Astrophysics Data System (ADS)

    Morris, Meg; Annand, John; Hornidge, David; Strandberg, Bruno

    2015-12-01

    Precise measurement of the neutron scalar polarizabilities has been a lasting challenge because of the lack of a free-neutron target. Led by the University of Glasgow and the Mount Allison University groups of the A2 collaboration in Mainz, Germany, preparations have begun to test a recent theoretical model with an active helium target with the hope of determining these elusive quantities with small statistical, systematic, and model-dependent errors. Apparatus testing and background-event simulations have been carried out, with the full experiment projected to run in 2015. Once determined, these values can be applied to help understand quantum chromodynamics in the nonperturbative region.

  4. Tumour necrosis factor (TNF-alpha) in leishmaniasis. II. TNF-alpha-induced macrophage leishmanicidal activity is mediated by nitric oxide from L-arginine.

    PubMed Central

    Liew, F Y; Li, Y; Millott, S

    1990-01-01

    Peritoneal macrophages from CBA mice incubated with recombinant murine tumour necrosis factor (TNF-alpha) are effective in killing the protozoa parasite Leishmania major in vitro. The leishmanicidal activity is directly correlated with the level of nitrite (NO2-) in the culture supernatants. The killing of intracellular parasites can be completely inhibited by L-NG-monomethyl arginine (L-NMMA), a specific inhibitor of the L-arginine:nitric oxide (NO) pathway. The level of NO2-, which is also a measurement of NO production, in the culture supernatant of TNF-alpha-activated macrophages can be progressively decreased to basal level with increasing concentrations of L-NMMA, but not with its D-enantiomer, D-NMMA. These data demonstrate that NO is an important effector mechanism in the TNF-alpha-induced macrophage killing of intracellular protozoa. PMID:2279740

  5. Decreased circulation time offsets increased efficacy of PEGylated nanocarriers targeting folate receptors of glioma

    NASA Astrophysics Data System (ADS)

    McNeeley, Kathleen M.; Annapragada, Ananth; Bellamkonda, Ravi V.

    2007-09-01

    Liposomal and other nanocarrier based drug delivery vehicles can localize to tumours through passive and/or active targeting. Passively targeted liposomal nanocarriers accumulate in tumours via 'leaky' vasculature through the enhanced permeability and retention (EPR) effect. Passive accumulation depends upon the circulation time and the degree of tumour vessel 'leakiness'. After extravasation, actively targeted liposomal nanocarriers efficiently deliver their payload by receptor-mediated uptake. However, incorporation of targeting moieties can compromise circulation time in the blood due to recognition and clearance by the reticuloendothelial system, decreasing passive accumulation. Here, we compare the efficacy of passively targeted doxorubicin-loaded PEGylated liposomal nanocarriers to that of actively targeted liposomal nanocarriers in a rat 9L brain tumour model. Although folate receptor (FR)-targeted liposomal nanocarriers had significantly reduced blood circulation time compared to PEGylated liposomal nanocarriers; intratumoural drug concentrations both at 20 and 50 h after administration were equal for both treatments. Both treatments significantly increased tumour inoculated animal survival by 60-80% compared to non-treated controls, but no difference in survival was observed between FR-targeted and passively targeted nanocarriers. Therefore, alternate approaches allowing for active targeting without compromising circulation time may be important for fully realizing the benefits of receptor-mediated active targeting of gliomas.

  6. Reversible, activity-dependent targeting of profilin to neuronal nuclei

    SciTech Connect

    Birbach, Andreas . E-mail: andreas.birbach@lbicr.lbg.ac.at; Verkuyl, J. Martin; Matus, Andrew . E-mail: aim@fmi.ch

    2006-07-15

    The actin cytoskeleton in pyramidal neurons plays a major role in activity-dependent processes underlying neuronal plasticity. The small actin-binding protein profilin shows NMDA receptor-dependent accumulation in dendritic spines, which is correlated with suppression of actin dynamics and long-term stabilization of synaptic morphology. Here we show that following NMDA receptor activation profilin also accumulates in the nucleus of hippocampal neurons via a process involving rearrangement of the actin cytoskeleton. This simultaneous targeting to dendritic spines and the cell nucleus suggests a novel mechanism of neuronal plasticity in which profilin both tags activated synapses and influences nuclear events.

  7. Exceptional antineoplastic activity of a dendritic-cell-targeted vaccine loaded with a Listeria peptide proposed against metastatic melanoma

    PubMed Central

    Calderon-Gonzalez, Ricardo; Bronchalo-Vicente, Lucia; Freire, Javier; Frande-Cabanes, Elisabet; Alaez-Alvarez, Lidia; Gomez-Roman, Javier; Yañez-Diaz, Sonsóles; Alvarez-Dominguez, Carmen

    2016-01-01

    Vaccination with dendritic cells (DCs) is proposed to induce lasting responses against melanoma but its survival benefit in patients needs to be demonstrated. We propose a DC-targeted vaccine loaded with a Listeria peptide with exceptional anti-tumour activity to prevent metastasis of melanoma. Mice vaccinated with vaccines based on DCs loaded with listeriolysin O peptide (91–99) (LLO91–99) showed clear reduction of metastatic B16OVA melanoma size and adhesion, prevention of lung metastasis, enhanced survival, and reversion of immune tolerance. Robust innate and specific immune responses explained the efficiency of DC-LLO91–99 vaccines against B16OVA melanoma. The noTable features of this vaccine related to melanoma reduction were: expansion of immune-dominant LLO91–99-specific CD8 T cells that helped to expand melanoma-specific CD8+ T cells; high numbers of tumour-infiltrating lymphocytes with a cytotoxic phenotype; and a decrease in CD4+CD25high regulatory T cells. This vaccine might be a useful alternative treatment for advanced melanoma, alone or in combination with other therapies. PMID:26942874

  8. Tumours of the lung

    PubMed Central

    Stünzi, H.; Head, K. W.; Nielsen, S. W.

    1974-01-01

    Lung tumours are not common in domestic animals; there has not been the increase in epidermoid carcinomas and anaplastic small-cell carcinomas that has occurred in man this century. Adenocarcinoma is the most common type in animals. The biological behaviour of each type of tumour in animals seems to be much the same as in man. The tumours are described histologically, the main categories being: epidermoid carcinoma, anaplastic carcinoma, adenocarcinoma, combined epidermoid and adenocarcinoma, carcinoid tumours, bronchial gland tumours, benign tumours, and sarcomas. ImagesFig. 13Fig. 14Fig. 15Fig. 16Fig. 1Fig. 2Fig. 3Fig. 4Fig. 5Fig. 6Fig. 7Fig. 8Fig. 9Fig. 10Fig. 11Fig. 12 PMID:4371738

  9. Optimising delineation accuracy of tumours in PET for radiotherapy planning using blind deconvolution

    PubMed Central

    Guvenis, A.; Koc, A.

    2015-01-01

    Positron emission tomography (PET) imaging has been proven to be useful in radiotherapy planning for the determination of the metabolically active regions of tumours. Delineation of tumours, however, is a difficult task in part due to high noise levels and the partial volume effects originating mainly from the low camera resolution. The goal of this work is to study the effect of blind deconvolution on tumour volume estimation accuracy for different computer-aided contouring methods. The blind deconvolution estimates the point spread function (PSF) of the imaging system in an iterative manner in a way that the likelihood of the given image being the convolution output is maximised. In this way, the PSF of the imaging system does not need to be known. Data were obtained from a NEMA NU-2 IQ-based phantom with a GE DSTE-16 PET/CT scanner. The artificial tumour diameters were 13, 17, 22, 28 and 37 mm with a target/background ratio of 4:1. The tumours were delineated before and after blind deconvolution. Student's two-tailed paired t-test showed a significant decrease in volume estimation error (p < 0.001) when blind deconvolution was used in conjunction with computer-aided delineation methods. A manual delineation confirmation demonstrated an improvement from 26 to 16 % for the artificial tumour of size 37 mm while an improvement from 57 to 15 % was noted for the small tumour of 13 mm. Therefore, it can be concluded that blind deconvolution of reconstructed PET images may be used to increase tumour delineation accuracy. PMID:25836686

  10. Buoyancy-activated cell sorting using targeted biotinylated albumin microbubbles.

    PubMed

    Liou, Yu-Ren; Wang, Yu-Hsin; Lee, Chia-Ying; Li, Pai-Chi

    2015-01-01

    Cell analysis often requires the isolation of certain cell types. Various isolation methods have been applied to cell sorting, including fluorescence-activated cell sorting and magnetic-activated cell sorting. However, these conventional approaches involve exerting mechanical forces on the cells, thus risking cell damage. In this study we applied a novel isolation method called buoyancy-activated cell sorting, which involves using biotinylated albumin microbubbles (biotin-MBs) conjugated with antibodies (i.e., targeted biotin-MBs). Albumin MBs are widely used as contrast agents in ultrasound imaging due to their good biocompatibility and stability. For conjugating antibodies, biotin is conjugated onto the albumin MB shell via covalent bonds and the biotinylated antibodies are conjugated using an avidin-biotin system. The albumin microbubbles had a mean diameter of 2 μm with a polydispersity index of 0.16. For cell separation, the MDA-MB-231 cells are incubated with the targeted biotin-MBs conjugated with anti-CD44 for 10 min, centrifuged at 10 g for 1 min, and then allowed 1 hour at 4 °C for separation. The results indicate that targeted biotin-MBs conjugated with anti-CD44 antibodies can be used to separate MDA-MB-231 breast cancer cells; more than 90% of the cells were collected in the MB layer when the ratio of the MBs to cells was higher than 70:1. Furthermore, we found that the separating efficiency was higher for targeted biotin-MBs than for targeted avidin-incorporated albumin MBs (avidin-MBs), which is the most common way to make targeted albumin MBs. We also demonstrated that the recovery rate of targeted biotin-MBs was up to 88% and the sorting purity was higher than 84% for a a heterogenous cell population containing MDA-MB-231 cells (CD44(+)) and MDA-MB-453 cells (CD44-), which are classified as basal-like breast cancer cells and luminal breast cancer cells, respectively. Knowing that the CD44(+) is a commonly used cancer-stem-cell biomarker, our

  11. Buoyancy-Activated Cell Sorting Using Targeted Biotinylated Albumin Microbubbles

    PubMed Central

    Liou, Yu-Ren; Wang, Yu-Hsin; Lee, Chia-Ying; Li, Pai-Chi

    2015-01-01

    Cell analysis often requires the isolation of certain cell types. Various isolation methods have been applied to cell sorting, including florescence-activated cell sorting and magnetic-activated cell sorting. However, these conventional approaches involve exerting mechanical forces on the cells, thus risking cell damage. In this study we applied a novel isolation method called buoyancy-activated cell sorting, which involves using biotinylated albumin microbubbles (biotin-MBs) conjugated with antibodies (i.e., targeted biotin-MBs). Albumin MBs are widely used as contrast agents in ultrasound imaging due to their good biocompatibility and stability. For conjugating antibodies, biotin is conjugated onto the albumin MB shell via covalent bonds and the biotinylated antibodies are conjugated using an avidin-biotin system. The albumin microbubbles had a mean diameter of 2μm with a polydispersity index of 0.16. For cell separation, the MDA-MB-231 cells are incubated with the targeted biotin-MBs conjugated with anti-CD44 for 10 min, centrifuged at 10g for 1 min, and then allowed 1 hour at 4°C for separation. The results indicate that targeted biotin-MBs conjugated with anti-CD44 antibodies can be used to separate MDA-MB-231 breast cancer cells; more than 90% of the cells were collected in the MB layer when the ratio of the MBs to cells was higher than 70:1. Furthermore, we found that the separating efficiency was higher for targeted biotin-MBs than for targeted avidin-incorporated albumin MBs (avidin-MBs), which is the most common way to make targeted albumin MBs. We also demonstrated that the recovery rate of targeted biotin-MBs was up to 88% and the sorting purity was higher than 84% for a a heterogenous cell population containing MDA-MB-231 cells (CD44+) and MDA-MB-453 cells (CD44–), which are classified as basal-like breast cancer cells and luminal breast cancer cells, respectively. Knowing that the CD44+ is a commonly used cancer-stem-cell biomarker, our targeted

  12. Yin Yang 1-mediated epigenetic silencing of tumour-suppressive microRNAs activates nuclear factor-κB in hepatocellular carcinoma.

    PubMed

    Tsang, Daisy P F; Wu, William K K; Kang, Wei; Lee, Ying-Ying; Wu, Feng; Yu, Zhuo; Xiong, Lei; Chan, Anthony W; Tong, Joanna H; Yang, Weiqin; Li, May S M; Lau, Suki S; Li, Xiangchun; Lee, Sau-Dan; Yang, Yihua; Lai, Paul B S; Yu, Dae-Yeul; Xu, Gang; Lo, Kwok-Wai; Chan, Matthew T V; Wang, Huating; Lee, Tin L; Yu, Jun; Wong, Nathalie; Yip, Kevin Y; To, Ka-Fai; Cheng, Alfred S L

    2016-04-01

    Enhancer of zeste homolog 2 (EZH2) catalyses histone H3 lysine 27 trimethylation (H3K27me3) to silence tumour-suppressor genes in hepatocellular carcinoma (HCC) but the process of locus-specific recruitment remains elusive. Here we investigated the transcription factors involved and the molecular consequences in HCC development. The genome-wide distribution of H3K27me3 was determined by chromatin immunoprecipitation coupled with high-throughput sequencing or promoter array analyses in HCC cells from hepatitis B virus (HBV) X protein transgenic mouse and human cell models. Transcription factor binding site analysis was performed to identify EZH2-interacting transcription factors followed by functional characterization. Our cross-species integrative analysis revealed a crucial link between Yin Yang 1 (YY1) and EZH2-mediated H3K27me3 in HCC. Gene expression analysis of human HBV-associated HCC specimens demonstrated concordant overexpression of YY1 and EZH2, which correlated with poor survival of patients in advanced stages. The YY1 binding motif was significantly enriched in both in vivo and in vitro H3K27me3-occupied genes, including genes for 15 tumour-suppressive microRNAs. Knockdown of YY1 reduced not only global H3K27me3 levels, but also EZH2 and H3K27me3 promoter occupancy and DNA methylation, leading to the transcriptional up-regulation of microRNA-9 isoforms in HCC cells. Concurrent EZH2 knockdown and 5-aza-2'-deoxycytidine treatment synergistically increased the levels of microRNA-9, which reduced the expression and transcriptional activity of nuclear factor-κB (NF-κB). Functionally, YY1 promoted HCC tumourigenicity and inhibited apoptosis of HCC cells, at least partially through NF-κB activation. In conclusion, YY1 overexpression contributes to EZH2 recruitment for H3K27me3-mediated silencing of tumour-suppressive microRNAs, thereby activating NF-κB signalling in hepatocarcinogenesis. PMID:26800240

  13. Inhibition of Lysyl Oxidase and Lysyl Oxidase-Like Enzymes Has Tumour-Promoting and Tumour-Suppressing Roles in Experimental Prostate Cancer

    PubMed Central

    Nilsson, Maria; Adamo, Hanibal; Bergh, Anders; Halin Bergström, Sofia

    2016-01-01

    Lysyl oxidase (LOX) and LOX-like (LOXL) enzymes are key players in extracellular matrix deposition and maturation. LOX promote tumour progression and metastasis, but it may also have tumour-inhibitory effects. Here we show that orthotopic implantation of rat prostate AT-1 tumour cells increased LOX and LOXLs mRNA expressions in the tumour and in the surrounding non-malignant prostate tissue. Inhibition of LOX enzymes, using Beta-aminopropionitrile (BAPN), initiated before implantation of AT-1 cells, reduced tumour growth. Conversely, treatment that was started after the tumours were established resulted in unaffected or increased tumour growth. Moreover, treatment with BAPN did not suppress the formation of spontaneous lymph node metastases, or lung tumour burden, when tumour cells were injected intravenously. A temporal decrease in collagen fibre content, which is a target for LOX, was observed in tumours and in the tumour-adjacent prostate tissue. This may explain why early BAPN treatment is more effective in inhibiting tumour growth compared to treatment initiated later. Our data suggest that the enzymatic function of the LOX family is context-dependent, with both tumour-suppressing and tumour-promoting properties in prostate cancer. Further investigations are needed to understand the circumstances under which LOX inhibition may be used as a therapeutic target for cancer patients. PMID:26804196

  14. Autophagy-induced RelB/p52 activation mediates tumour-associated macrophage repolarisation and suppression of hepatocellular carcinoma by natural compound baicalin.

    PubMed

    Tan, H-Y; Wang, N; Man, K; Tsao, S-W; Che, C-M; Feng, Y

    2015-01-01

    The plasticity of tumour-associated macrophages (TAMs) has implicated an influential role in hepatocellular carcinoma (HCC). Repolarisation of TAM towards M1 phenotype characterises an immune-competent microenvironment that favours tumour regression. To investigate the role and mechanism of TAM repolarisation in suppression of HCC by a natural compound baicalin, Orthotopic HCC implantation model was used to investigate the effect of baicalin on HCC; liposome-clodronate was introduced to suppress macrophage populations in mice; bone marrow-derived monocytes (BMDMs) were induced to unpolarised, M1-like, M2-like macrophages and TAM using different conditioned medium. We observed that oral administration of baicalin (50 mg/kg) completely blocked orthotopic growth of implanted HCC. Suppression of HCC by baicalin was diminished when mice macrophage was removed by clodronate treatment. Baicalin induced repolarisation of TAM to M1-like phenotype without specific toxicity to either phenotype of macrophages. Baicalin initiated TAM reprogramming to M1-like macrophage, and promoted pro-inflammatory cytokines production. Co-culturing of HCC cells with baicalin-treated TAMs resulted in reduced proliferation and motility in HCC. Baicalin had minimal effect on derivation of macrophage polarisation factors by HCC cells, while directly induced repolarisation of TAM and M2-like macrophage. This effect was associated with elevated autophagy, and transcriptional activation of RelB/p52 pathway. Suppression of autophagy or RelB abolished skewing of baicalin-treated TAM. Autophagic degradation of TRAF2 in baicalin-treated TAM might be responsible for RelB/p52 activation. Our findings unveil the essential role of TAM repolarisation in suppressive effect of baicalin on HCC, which requires autophagy-associated activation of RelB/p52. PMID:26492375

  15. Autophagy-induced RelB/p52 activation mediates tumour-associated macrophage repolarisation and suppression of hepatocellular carcinoma by natural compound baicalin

    PubMed Central

    Tan, H-Y; Wang, N; Man, K; Tsao, S-W; Che, C-M; Feng, Y

    2015-01-01

    The plasticity of tumour-associated macrophages (TAMs) has implicated an influential role in hepatocellular carcinoma (HCC). Repolarisation of TAM towards M1 phenotype characterises an immune-competent microenvironment that favours tumour regression. To investigate the role and mechanism of TAM repolarisation in suppression of HCC by a natural compound baicalin, Orthotopic HCC implantation model was used to investigate the effect of baicalin on HCC; liposome-clodronate was introduced to suppress macrophage populations in mice; bone marrow-derived monocytes (BMDMs) were induced to unpolarised, M1-like, M2-like macrophages and TAM using different conditioned medium. We observed that oral administration of baicalin (50 mg/kg) completely blocked orthotopic growth of implanted HCC. Suppression of HCC by baicalin was diminished when mice macrophage was removed by clodronate treatment. Baicalin induced repolarisation of TAM to M1-like phenotype without specific toxicity to either phenotype of macrophages. Baicalin initiated TAM reprogramming to M1-like macrophage, and promoted pro-inflammatory cytokines production. Co-culturing of HCC cells with baicalin-treated TAMs resulted in reduced proliferation and motility in HCC. Baicalin had minimal effect on derivation of macrophage polarisation factors by HCC cells, while directly induced repolarisation of TAM and M2-like macrophage. This effect was associated with elevated autophagy, and transcriptional activation of RelB/p52 pathway. Suppression of autophagy or RelB abolished skewing of baicalin-treated TAM. Autophagic degradation of TRAF2 in baicalin-treated TAM might be responsible for RelB/p52 activation. Our findings unveil the essential role of TAM repolarisation in suppressive effect of baicalin on HCC, which requires autophagy-associated activation of RelB/p52. PMID:26492375

  16. AMPK activation: a therapeutic target for type 2 diabetes?

    PubMed Central

    Coughlan, Kimberly A; Valentine, Rudy J; Ruderman, Neil B; Saha, Asish K

    2014-01-01

    Type 2 diabetes (T2D) is a metabolic disease characterized by insulin resistance, β-cell dysfunction, and elevated hepatic glucose output. Over 350 million people worldwide have T2D, and the International Diabetes Federation projects that this number will increase to nearly 600 million by 2035. There is a great need for more effective treatments for maintaining glucose homeostasis and improving insulin sensitivity. AMP-activated protein kinase (AMPK) is an evolutionarily conserved serine/threonine kinase whose activation elicits insulin-sensitizing effects, making it an ideal therapeutic target for T2D. AMPK is an energy-sensing enzyme that is activated when cellular energy levels are low, and it signals to stimulate glucose uptake in skeletal muscles, fatty acid oxidation in adipose (and other) tissues, and reduces hepatic glucose production. There is substantial evidence suggesting that AMPK is dysregulated in animals and humans with metabolic syndrome or T2D, and that AMPK activation (physiological or pharmacological) can improve insulin sensitivity and metabolic health. Numerous pharmacological agents, natural compounds, and hormones are known to activate AMPK, either directly or indirectly – some of which (for example, metformin and thiazolidinediones) are currently used to treat T2D. This paper will review the regulation of the AMPK pathway and its role in T2D, some of the known AMPK activators and their mechanisms of action, and the potential for future improvements in targeting AMPK for the treatment of T2D. PMID:25018645

  17. Novel therapeutic targets for pancreatic cancer

    PubMed Central

    Tang, Shing-Chun; Chen, Yang-Chao

    2014-01-01

    Pancreatic cancer has become the fourth leading cause of cancer death in the last two decades. Only 3%-15% of patients diagnosed with pancreatic cancer had 5 year survival rate. Drug resistance, high metastasis, poor prognosis and tumour relapse contributed to the malignancies and difficulties in treating pancreatic cancer. The current standard chemotherapy for pancreatic cancer is gemcitabine, however its efficacy is far from satisfactory, one of the reasons is due to the complex tumour microenvironment which decreases effective drug delivery to target cancer cell. Studies of the molecular pathology of pancreatic cancer have revealed that activation of KRAS, overexpression of cyclooxygenase-2, inactivation of p16INK4A and loss of p53 activities occurred in pancreatic cancer. Co-administration of gemcitabine and targeting the molecular pathological events happened in pancreatic cancer has brought an enhanced therapeutic effectiveness of gemcitabine. Therefore, studies looking for novel targets in hindering pancreatic tumour growth are emerging rapidly. In order to give a better understanding of the current findings and to seek the direction in future pancreatic cancer research; in this review we will focus on targets suppressing tumour metastatsis and progression, KRAS activated downstream effectors, the relationship of Notch signaling and Nodal/Activin signaling with pancreatic cancer cells, the current findings of non-coding RNAs in inhibiting pancreatic cancer cell proliferation, brief discussion in transcription remodeling by epigenetic modifiers (e.g., HDAC, BMI1, EZH2) and the plausible therapeutic applications of cancer stem cell and hyaluronan in tumour environment. PMID:25152585

  18. The Platin-X series: activation, targeting, and delivery.

    PubMed

    Basu, Uttara; Banik, Bhabatosh; Wen, Ru; Pathak, Rakesh K; Dhar, Shanta

    2016-08-16

    Anticancer platinum (Pt) complexes have long been considered to be one of the biggest success stories in the history of medicinal inorganic chemistry. Yet there remains the hunt for the "magic bullet" which can satisfy the requirements of an effective chemotherapeutic drug formulation. Pt(iv) complexes are kinetically more inert than the Pt(ii) congeners and offer the opportunity to append additional functional groups/ligands for prodrug activation, tumor targeting, or drug delivery. The ultimate aim of functionalization is to enhance the tumor selective action and attenuate systemic toxicity of the drugs. Moreover, an increase in cellular accumulation to surmount the resistance of the tumor against the drugs is also of paramount importance in drug development and discovery. In this review, we will address the attempts made in our lab to develop Pt(iv) prodrugs that can be activated and delivered using targeted nanotechnology-based delivery platforms. PMID:27493131

  19. Feasibility study of an active target for the MEG experiment

    NASA Astrophysics Data System (ADS)

    Papa, A.; Cavoto, G.; Ripiccini, E.

    2014-03-01

    We consider the possibility to have an active target for the upgrade of the MEG experiment (MEG II). The active target should work as (1) a beam monitoring, to continuously measure the muon stopping rate and therefore provide a direct evaluation of the detector acceptance (or an absolute normalization of the stopped muon); and as (2) an auxiliary device for the spectrometer, to improve the determination of the muon decay vertex and consequently to achieve a better positron momentum and angular resolutions, detecting the positron from the muon decay. In this work we studied the feasibility of detecting minimum ionizing particle with a single layer of 250 μm fiber and the capability to discriminate between the signal induced by either a muon or a positron.

  20. Molecular modelling, synthesis, cytotoxicity and anti-tumour mechanisms of 2-aryl-6-substituted quinazolinones as dual-targeted anti-cancer agents

    PubMed Central

    Hour, M J; Lee, K H; Chen, T L; Lee, K T; Zhao, Yu; Lee, H Z

    2013-01-01

    Background and Purpose Our previous study demonstrated that 6-(pyrrolidin-1-yl)-2-(3-methoxyphenyl)quinazolin-4-one (HMJ38) was a potent anti-tubulin agent. Here, HMJ38 was used as a lead compound to develop more potent anti-cancer agents and to examine the anti-cancer mechanisms. Experimental Approach Using computer-aided drug design, 2-aryl-6-substituted quinazolinones (MJ compounds) were designed and synthesized by introducing substituents at C-2 and C-6 positions of HMJ38. The cytotoxicity of MJ compounds towards human cancer cells was examined by Trypan blue exclusion assay. Microtubule distribution was visualized using TubulinTracker™ Green reagent. Protein expression of cell cycle regulators and JNK was assessed by Western blot analysis. Key Results Compounds MJ65–70 exhibited strong anti-proliferative effects towards melanoma M21, lung squamous carcinoma CH27, lung non-small carcinoma H460, hepatoma Hep3B and oral cancer HSC-3 cells, with one compund MJ66 (6-(pyrrolidin-1-yl)-2-(naphthalen-1-yl)quinazolin-4-one) highly active against M21 cells (IC50 about 0.033 μM). Treatment of CH27 or HSC-3 cells with MJ65–70 resulted in significant mitotic arrest accompanied by increasing multiple asters of microtubules. JNK protein expression was involved in the MJ65–70-induced CH27 and M21 cell death. Consistent with the cell cycle arrest at G2/M phase, marked increases in cyclin B1 and Bcl-2 phosphorylation were also observed, after treatment with MJ65–70. Conclusions and Implication MJ65–70 are dual-targeted, tubulin- and JNK-binding, anti-cancer agents and induce cancer cell death through up-regulation of JNK and interfering in the dynamics of tubulin. Our work provides a new strategy and mechanism for developing dual-targeted anti-cancer drugs, contributing to clinical anti-cancer drug discovery and application. PMID:23638624

  1. MET is required for the recruitment of anti-tumoural neutrophils

    PubMed Central

    Finisguerra, Veronica; Di Conza, Giusy; Di Matteo, Mario; Serneels, Jens; Costa, Sandra; Thompson, A.A. Roger; Wauters, Els; Walmsley, Sarah; Prenen, Hans; Granot, Zvi; Casazza, Andrea; Mazzone, Massimiliano

    2015-01-01

    Mutations or amplification of the MET proto-oncogene are involved in the pathogenesis of several tumours1-4, which rely on the constitutive engagement of this pathway for their growth and survival1,5. However, MET is expressed not only by cancer cells but also by tumour-associated stromal cells although its precise role in this compartment is not well characterized6-11. Here, we show that MET is required for neutrophil chemoattraction and cytotoxicity in response to its ligand HGF. Met deletion in neutrophils enhances tumour growth and metastasis. This phenotype correlates with reduced neutrophil infiltration to both primary tumour and metastatic site. Similarly, Met is necessary for neutrophil transudation during colitis, skin rash or peritonitis. Mechanistically, Met is induced by tumour-derived TNF-α or other inflammatory stimuli in both mouse and human neutrophils. This induction is instrumental for neutrophil transmigration across an activated endothelium and iNOS production upon HGF stimulation. Consequently, HGF/MET-dependent nitric oxide release by neutrophils promotes cancer cell killing, which abates tumour growth and metastasis. Following systemic administration of a MET kinase inhibitor, we prove that the therapeutic benefit of MET targeting in cancer cells is partly countered by the pro-tumoural effect rising from MET blockade in neutrophils. Our work identifies an unprecedented role of MET in neutrophils, suggests a potential “Achilles’ heel” of MET-targeted therapies in cancer, and supports the rationale for evaluating anti-MET drugs in certain inflammatory diseases. PMID:25985180

  2. Oncolytic virotherapy for advanced liver tumours

    PubMed Central

    Chang, Ju-Fang; Chen, Pei-Jer; Sze, Daniel Y; Reid, Tony; Bartlett, David; Kirn, David H; Liu, Ta-Chiang

    2009-01-01

    Primary and metastatic neoplasms of the liver account for more than a million deaths per year worldwide. Despite decades of research, effective novel therapies for these cancers are urgently needed. Oncolytic virotherapeutics represent a novel class of pharmacophore that holds promise for the treatment of hepatic neoplasms. Cancer-specific replication is followed by oncolysis, virus spreading and infection of adjacent cancer cells. This process is then repeated. Virotherapeutics target multiple genetic pathways involved in carcino-genesis, and demonstrate activity against apoptosis-resistant tumour cells. This platform can also exploit the advantage of multiple intrinsic anti-cancer therapeutic mechanisms, combining direct viral oncolysis with therapeutic transgene expression. Recent advances in pre-clinical and clinical studies are revealing the potential of this unique therapeutic class, in particular for liver cancers. This review summarizes the available data on applying oncolytic virotherapeutics to hepatic neoplasms to date, and discusses the challenges and future directions for virotherapy. PMID:19175689

  3. Active multispectral near-IR detection of small surface targets

    NASA Astrophysics Data System (ADS)

    de Jong, Arie N.; Winkel, Hans; Roos, Marco J. J.

    2001-10-01

    The detection and identification of small surface targets with Electro-Optical sensors is seriously hampered by ground clutter, leading to false alarms and reduced detection probabilities. Active ground illumination can improve the detection performance of EO sensors compared to passive skylight illumination because of the knowledge of the illumination level and of its temporal stability. Sun and sky cannot provide this due to the weather variability. In addition multispectral sensors with carefully chosen spectral bands ranging from the visual into the near IR from 400-2500 nm wavelength can take benefit of a variety of cheap active light sources, ranging from lasers to Xenon or halogen lamps. Results are presented, obtained with a two- color laser scanner with one wavelength in the chlorophyll absorption dip. Another active scanner is described operating at 4 wavebands between 1400 and 2300 nm, using tungsten halogen lamps. Finally a simple TV camera was used with either a ste of narrow band spectral filters or polarization filters in front of the lamps. The targets consisted of an array of mixed objects, most of them real mines. The results how great promise in enhancing the detection and identification probabilities of EO sensors against small surface targets.

  4. Target system of IFMIF/EVEDA in Japanese activities

    NASA Astrophysics Data System (ADS)

    Ida, M.; Fukada, S.; Furukawa, T.; Hirakawa, Y.; Horiike, H.; Kanemura, T.; Kondo, H.; Miyashita, M.; Nakamura, H.; Sigiura, H.; Suzuki, A.; Terai, T.; Tsuji, Y.; Ushimaru, H.; Watanabe, K.; Yagi, J.

    2011-10-01

    The Engineering Validation and Engineering Design Activities (EVEDA) of the International Fusion Materials Irradiation Facility (IFMIF) have been started. As Japanese activities for the target system, the EVEDA Lithium (Li) Test Loop to simulate hydraulic and impurity conditions of the IFMIF Li loop is under design. The feasibility of the thermo-mechanical structure of the target assembly and the replaceable back-plate made of F82H and 316L stainless steel is a key research subject. Toward final validation at the EVEDA loop, diagnostics systems applicable to the high-speed free-surface Li flow and hot traps to control nitrogen and hydrogen in Li loop have been investigated. In the remote handling subject of target assemblies and the replaceable back-plates activated by irradiation up to 50 dpa/y, lip welds on 316L-316L by laser and dissimilar metal welds on F82H-316L are necessary. Water experiments and hydraulic/thermo-mechanical analyses of the back-plate are underway.

  5. Brain activation underlying threat detection to targets of different races.

    PubMed

    Senholzi, Keith B; Depue, Brendan E; Correll, Joshua; Banich, Marie T; Ito, Tiffany A

    2015-01-01

    The current study examined blood oxygen level-dependent signal underlying racial differences in threat detection. During functional magnetic resonance imaging, participants determined whether pictures of Black or White individuals held weapons. They were instructed to make shoot responses when the picture showed armed individuals but don't shoot responses to unarmed individuals, with the cost of not shooting armed individuals being greater than that of shooting unarmed individuals. Participants were faster to shoot armed Blacks than Whites, but faster in making don't shoot responses to unarmed Whites than Blacks. Brain activity differed to armed versus unarmed targets depending on target race, suggesting different mechanisms underlying threat versus safety decisions. Anterior cingulate cortex was preferentially engaged for unarmed Whites than Blacks. Parietal and visual cortical regions exhibited greater activity for armed Blacks than Whites. Seed-based functional connectivity of the amygdala revealed greater coherence with parietal and visual cortices for armed Blacks than Whites. Furthermore, greater implicit Black-danger associations were associated with increased amygdala activation to armed Blacks, compared to armed Whites. Our results suggest that different neural mechanisms may underlie racial differences in responses to armed versus unarmed targets. PMID:26357911

  6. Minireview: Targeting GPCR Activated ERK Pathways for Drug Discovery

    PubMed Central

    Eishingdrelo, Haifeng; Kongsamut, Sathapana

    2013-01-01

    It has become clear in recent years that multiple signal transduction pathways are employed upon GPCR activation. One of the major cellular effectors activated by GPCRs is extracellular signal-regulated kinase (ERK). Both G-protein and β-arrestin mediated signaling pathways can lead to ERK activation. However, depending on activation pathway, the subcellular destination of activated ERK1/2 may be different. G-protein -dependent ERK activation results in the translocation of active ERK to the nucleus, whereas ERK activated via an arrestin-dependent mechanism remains largely in the cytoplasm. The subcellular location of activated ERK1/2 determines the downstream signaling cascade. Many substrates of ERK1/2 are found in the nucleus: nuclear transcription factors that participate in gene transcription, cell proliferation and differentiation. ERK1/2 substrates are also found in cytosol and other cellular organelles: they may play roles in translation, mitosis, apoptosis and cross-talk with other signaling pathways. Therefore, determining specific subcellular locations of activated ERK1/2 mediated by GPCR ligands would be important in correlating signaling pathways with cellular physiological functions. While GPCR-stimulated selective ERK pathway activation has been studied in several receptor systems, exploitation of these different signaling cascades for therapeutics has not yet been seriously pursued. Many old drug candidates were identified from screens based on G-protein signaling assays, and their activity on β-arrestin signaling pathways being mostly unknown, especially regarding their subcellular ERK pathways. With today’s knowledge of complicated GPCR signaling pathways, drug discovery can no longer rely on single-pathway approaches. Since ERK activation is an important signaling pathway and associated with many physiological functions, targeting the ERK pathway, especially specific subcellular activation pathways should provide new avenues for GPCR drug

  7. Telomere uncapping by the G-quadruplex ligand RHPS4 inhibits clonogenic tumour cell growth in vitro and in vivo consistent with a cancer stem cell targeting mechanism.

    PubMed

    Phatak, P; Cookson, J C; Dai, F; Smith, V; Gartenhaus, R B; Stevens, M F G; Burger, A M

    2007-04-23

    The pentacyclic acridinium methosulfate salt RHPS4 induces the 3'single-stranded guanine-rich telomeric overhang to fold into a G-quadruplex structure. Stabilisation of the latter is incompatible with an attachment of telomerase to the telomere and thus G-quadruplex ligands can effectively inhibit both the catalytic and capping functions of telomerase. In this study, we examined mechanisms underlying telomere uncapping by RHPS4 in uterus carcinoma cells (UXF1138L) with short telomeres and compared the susceptibility of bulk and clonogenic cancer cells to the G-quadruplex ligand. We show that treatment of UXF1138L cells with RHPS4 leads to the displacement of the telomerase catalytic subunit (hTERT) from the nucleus, induction of telomere-initiated DNA-damage signalling and chromosome fusions. We further report that RHPS4 is more potent against cancer cells that grow as colonies in soft agar than cells growing as monolayers. Human cord blood and HEK293T embryonic kidney cell colony forming units, however, were more resistant to RHPS4. RHPS4-treated UXF1138L xenografts had a decreased clonogenicity, showed loss of nuclear hTERT expression and an induction of mitotic abnormalities compared with controls. Although single-agent RHPS4 had limited in vivo efficacy, a combination of RHPS4 with the mitotic spindle poison Taxol caused tumour remissions and further enhancement of telomere dysfunction. PMID:17406367

  8. Telomere uncapping by the G-quadruplex ligand RHPS4 inhibits clonogenic tumour cell growth in vitro and in vivo consistent with a cancer stem cell targeting mechanism

    PubMed Central

    Phatak, P; Cookson, J C; Dai, F; Smith, V; Gartenhaus, R B; Stevens, M F G; Burger, A M

    2007-01-01

    The pentacyclic acridinium methosulfate salt RHPS4 induces the 3′single-stranded guanine-rich telomeric overhang to fold into a G-quadruplex structure. Stabilisation of the latter is incompatible with an attachment of telomerase to the telomere and thus G-quadruplex ligands can effectively inhibit both the catalytic and capping functions of telomerase. In this study, we examined mechanisms underlying telomere uncapping by RHPS4 in uterus carcinoma cells (UXF1138L) with short telomeres and compared the susceptibility of bulk and clonogenic cancer cells to the G-quadruplex ligand. We show that treatment of UXF1138L cells with RHPS4 leads to the displacement of the telomerase catalytic subunit (hTERT) from the nucleus, induction of telomere-initiated DNA-damage signalling and chromosome fusions. We further report that RHPS4 is more potent against cancer cells that grow as colonies in soft agar than cells growing as monolayers. Human cord blood and HEK293T embryonic kidney cell colony forming units, however, were more resistant to RHPS4. RHPS4-treated UXF1138L xenografts had a decreased clonogenicity, showed loss of nuclear hTERT expression and an induction of mitotic abnormalities compared with controls. Although single-agent RHPS4 had limited in vivo efficacy, a combination of RHPS4 with the mitotic spindle poison Taxol caused tumour remissions and further enhancement of telomere dysfunction. PMID:17406367

  9. Keratinocyte sensitization to tumour necrosis factor-induced nuclear factor kappa B activation by the E2 regulatory protein of human papillomaviruses.

    PubMed

    Boulabiar, Manel; Boubaker, Samir; Favre, Michel; Demeret, Caroline

    2011-10-01

    Human papillomavirus (HPV) life cycle requires extensive manipulation of cell signalling to provide conditions adequate for viral replication within the stratified epithelia. In this regard, we show that the E2 regulatory protein of α, β and μ-HPV genotypes enhances tumour necrosis factor (TNF)-induced activation of nuclear factor kappa B (NF-κB). This activation is mediated by the N-terminal domain of E2, but does not rely on its transcriptional properties. It is independent of the NF-κB regulator Tax1BP1, which nevertheless interacts with all the E2 proteins. E2 specifically activates NF-κB pathways induced by TNF, while interleukin-1-induced pathways are not affected. E2 stimulates the activating K63-linked ubiquitination of TRAF5, and interacts with both TRAF5 and TRAF6. Our data suggest that E2 potentiates TNF-induced NF-κB signalling mediated by TRAF5 activation through direct binding. Since NF-κB controls epithelial differentiation, this activity may be involved in the commitment of infected keratinocytes to proliferation arrest and differentiation, both required for the implementation of the productive viral cycle. PMID:21715600

  10. Targeting Gli Transcription Activation by Small Molecule Suppresses Tumor Growth

    PubMed Central

    Bosco-Clément, Geneviève; Zhang, Fang; Chen, Zhao; Zhou, Hai-Meng; Li, Hui; Mikami, Iwao; Hirata, Tomomi; Yagui-Beltran, Adam; Lui, Natalie; Do, Hanh T.; Cheng, Tiffany; Tseng, Hsin-Hui; Choi, Helen; Fang, Li-Tai; Kim, Il-Jin; Yue, Dongsheng; Wang, Changli; Zheng, Qingfeng; Fujii, Naoaki; Mann, Michael; Jablons, David M.; He, Biao

    2014-01-01

    Targeted inhibition of Hedgehog signaling at the cell membrane has been associated with anti-cancer activity in preclinical and early clinical studies. Hedgehog signaling involves activation of Gli transcription factors that can also be induced by alternative pathways. In this study we identified an interaction between Gli proteins and a transcription co-activator TAF9, and validated its functional relevance in regulating Gli transactivation. We also describe a novel, synthetic small molecule, FN1-8, that efficiently interferes with Gli/TAF9 interaction and down-regulate Gli/TAF9 dependent transcriptional activity. More importantly, FN1-8 suppresses cancer cell proliferation in vitro and inhibits tumor growth in vivo. Our results suggest that blocking Gli transactivation, a key control point of multiple oncogenic pathways, may be an effective anti-cancer strategy. PMID:23686308

  11. MicroRNAs 221 and 222 target p27Kip1 in Marek's disease virus-transformed tumour cell line MSB-1.

    PubMed

    Lambeth, Luke S; Yao, Yongxiu; Smith, Lorraine P; Zhao, Yuguang; Nair, Venugopal

    2009-05-01

    MicroRNAs (miRNAs) are a class of short RNAs that function as post-transcriptional suppressors of protein expression and are involved in a variety of biological processes, including oncogenesis. Several recent studies have implicated the involvement of miR-221 and miR-222 in tumorigenesis as these miRNAs are upregulated in a number of cancers and affect the expression of cell cycle regulatory proteins such as the cyclin-dependent kinase (cdk) inhibitor p27(Kip1). Marek's disease virus (MDV) is a highly oncogenic herpesvirus that affects poultry, causing acute neoplastic disease with lymphomatous lesions in several organs. MDV-encoded oncogenes such as Meq are directly implicated in the neoplastic transformation of T cells and have been well studied. More recently, however, the involvement of both host and virus-encoded miRNAs in the induction of MD lymphomas is being increasingly recognized. We analysed the miRNA expression profiles in the MDV-transformed lymphoblastoid cell line MSB-1 and found that endogenous miRNAs miR-221 and miR-222 were significantly upregulated. Demonstration of the conserved binding sites for these miRNAs in the chicken p27(Kip1) 3'-untranslated region sequence and the repression of luciferase activity of reporter constructs indicated that miR-221 and miR-222 target p27(Kip1) in these cells. We also found that overexpression of miR-221 and miR-222 decreased p27(Kip1) levels and that treatment with retrovirally expressed antagomiRs partially alleviated this suppression. These data show that an oncogenic herpesvirus, as in the case of many cancers, can exploit the miRNA machinery for suppressing cell cycle regulatory molecules such as p27(Kip1) in the induction and progression of T-cell lymphomas. PMID:19264608

  12. In vitro inhibition of human malignant brain tumour cell line proliferation by anti-urokinase-type plasminogen activator monoclonal antibodies.

    PubMed Central

    Abaza, M. S.; Shaban, F. A.; Narayan, R. K.; Atassi, M. Z.

    1998-01-01

    A brain tumour-associated marker, urokinase (UK), was investigated using rabbit anti-UK polyclonal and murine anti-UK monoclonal antibodies, which were prepared by immunization with low molecular weight UK (LMW-UK) and high molecular weight urokinase (HMW-UK) synthetic peptide respectively. The polyclonal antibody cross-reacted with both LMW-UK and HMW-UK, whereas the murine MAbs were specific for HMW-UK. These immunological probes were used to study urokinase in glioma extracts, tissues, sera and cell lines that had been prepared from primary cultures of freshly dissected gliomas. Radioimmunoassays showed that glioma extracts had much higher level (5- to 44-fold) of UK than normal human brain extracts. This result was confirmed by immunoblotting of electrophoresis gels of glioma and human brain extracts. Immunohistochemical study using anti-UK MAb demonstrated much higher levels of UK in glioma tissue than normal brain tissue. Immunohistochemical study using anti-UK MAbs localized UK on the cell surface of glioma cells. Anti-UK MAbs inhibited the proliferation of AA cell lines and GB cell lines (50% to > 90%) and exerted minor effects (< or = 20%) on normal human liver, intestine and lymphocyte cell lines. Taken together, these results suggest that anti-UK MAbs may have therapeutic potential for human gliomas and cancer metastasis. Images Figure 2 Figure 3 PMID:9862567

  13. Active targets for the study of nuclei far from stability

    NASA Astrophysics Data System (ADS)

    Beceiro-Novo, S.; Ahn, T.; Bazin, D.; Mittig, W.

    2015-09-01

    Weakly bound nuclear systems can be considered to represent a good testing-ground of our understanding of non-perturbative quantum systems. Reactions leading to bound and unbound states in systems with very unbalanced neutron-to-proton ratios are used to understand the properties of these systems. Radioactive beams with energies from below the Coulomb barrier up to several hundreds MeV/nucleon are now available, and with these beams, a broad variety of studies of nuclei near the drip-line can be performed. To compensate for the low intensity of secondary beams as compared to primary beams, thick targets and high efficiency detection is necessary. In this context, a new generation of detectors was developed, called active target detectors: the detector gas is used as target, and the determination of the reaction vertex in three dimensions allows for good resolution even with thick targets. The reaction products can be measured over essentially 4 π. The physics explored with these detectors together with the technology developed will be described.

  14. Tumour ablation: technical aspects

    PubMed Central

    Bodner, Gerd; Bale, Reto

    2009-01-01

    Abstract Image-guided percutaneous radiofrequency ablation (RFA) is a minimally invasive, relatively low-risk procedure for tumour treatment. Local recurrence and survival rates depend on the rate of complete ablation of the entire tumour including a sufficient margin of surrounding healthy tissue. Currently a variety of different RFA devices are available. The interventionalist must be able to predict the configuration and extent of the resulting ablation necrosis. Accurate planning and execution of RFA according to the size and geometry of the tumour is essential. In order to minimize complications, individualized treatment strategies may be necessary for tumours close to vital structures. This review examines the state-of-the art of different device technologies, approaches, and treatment strategies for percutaneous RFA of liver tumours. PMID:19965296

  15. Tumour tracking with scanned proton beams: assessing the accuracy and practicalities

    NASA Astrophysics Data System (ADS)

    van de Water, S.; Kreuger, R.; Zenklusen, S.; Hug, E.; Lomax, A. J.

    2009-11-01

    The potential of tumour tracking for active spot-scanned proton therapy was assessed. Using a 4D-dose calculation and simulated target motion, a tumour tracking algorithm has been implemented and applied to a simple target volume in both homogenous and heterogeneous in silico phantoms. For tracking and retracking (a hybrid solution combining tumour tracking and rescanning), three tracking modes were analysed: 'no tracking' (uncorrected irradiation of a moving target), 'perfect tracking' (no time delays and exact knowledge of target position) and 'imperfect tracking' (simulated time delays or position prediction errors). For all plans, dose homogeneity in the target volume was assessed as the difference between D5 and D95 in the CTV. For the homogeneous phantom, perfect tracking could retrieve nominal dose homogeneity for all motion phases and amplitudes while severe deterioration of treatment outcomes was found for imperfect tracking. The use of retracking reduced the sensitivity to position errors significantly in the homogeneous phantom. In the heterogeneous phantoms (simulated rib proximal to target), the nominal dose homogeneity could not be obtained with perfect tracking. Adjustments in pencil beam positions could cause pencil beams to deform under the influence of the bone, resulting in loss of dose homogeneity. As retracking was not capable of reducing these effects, rescanning provided the best treatment outcomes for moving heterogeneous targets in this study.

  16. A numerically optimized active shield for improved TMS targeting

    PubMed Central

    Hernandez-Garcia, Luis; Hall, Timothy; Gomez, Luis; Michielssen, Eric

    2010-01-01

    Transcranial magnetic stimulation (TMS) devices suffer of poor targeting and penetration depth. A new approach to designing TMS coils is introduced in order to improve the focus of the stimulation region through the use of actively shielded probes. Iterative optimization techniques were used to design different active shielding coils for TMS probes. The new approach aims to increase the amount of energy deposited in a thin cylindrical region below the probe relative to the energy deposited elsewhere in the region (“sharpness”), while simultaneously increase the induced electric field deep in the target region relative to the surface (“penetration”). After convergence, the resulting designs showed that there is a clear tradeoff between sharpness and penetration that can be controlled by the choice of a tuning parameter. The resulting designs were tested on a realistic human head conductivity model, taking the contribution from surface charges into account. The design of choice reduced penetration depths by 16.7%. The activated surface area was reduced by 24.1 % and the volume of the activation was reduced from 42.6% by the shield. Restoring the lost penetration could be achieved by increasing the total power to the coil by 16.3%, but in that case, the stimulated volume reduction was only 13.1% and there was a slight increase in the stimulated surface area (2.9 %) PMID:20965451

  17. Factor XI and Contact Activation as Targets for Antithrombotic Therapy

    PubMed Central

    Gailani, David; Bane, Charles E.; Gruber, Andras

    2015-01-01

    Summary The most commonly used anticoagulants produce therapeutic antithrombotic effects either by inhibiting thrombin or factor Xa, or by lowering the plasma levels of the precursors of these key enzymes, prothrombin and factor X. These drugs do not distinguish between thrombin generation contributing to thrombosis from thrombin generation required for hemostasis. Thus, anticoagulants increase bleeding risk, and many patients who would benefit from therapy go untreated because of comorbidities that place them at unacceptable risk for hemorrhage. Studies in animals demonstrate that components of the plasma contact activation system contribute to experimentally-induced thrombosis, despite playing little or no role in hemostasis. Attention has focused on factor XII, the zymogen of a protease (factor XIIa) that initiates contact activation when blood is exposed to foreign surfaces; and factor XI, the zymogen of the protease factor XIa, which links contact activation to the thrombin generation mechanism. In the case of factor XI, epidemiologic data indicate this protein contributes to stroke and venous thromboembolism, and perhaps myocardial infarction, in humans. A phase 2 trial showing that reduction of factor XI may be more effective than low-molecular-weight heparin at preventing venous thrombosis during knee replacement surgery provides proof of concept for the premise that an antithrombotic effect can be uncoupled from an anticoagulant effect in humans by targeting components of contact activation. Here we review data on the role of factor XI and factor XII in thrombosis, and results of pre-clinical and human trials for therapies targeting these proteins. PMID:25976012

  18. HER2 activating mutations are targets for colorectal cancer treatment

    PubMed Central

    Kavuri, Shyam M.; Jain, Naveen; Galimi, Francesco; Cottino, Francesca; Leto, Simonetta M.; Migliardi, Giorgia; Searleman, Adam C.; Shen, Wei; Monsey, John; Trusolino, Livio; Jacobs, Samuel A.; Bertotti, Andrea; Bose, Ron

    2015-01-01

    The Cancer Genome Atlas project identified HER2 somatic mutations and gene amplification in 7% of colorectal cancer patients. Introduction of the HER2 mutations, S310F, L755S, V777L, V842I, and L866M, into colon epithelial cells increased signaling pathways and anchorage-independent cell growth, indicating that they are activating mutations. Introduction of these HER2 activating mutations into colorectal cancer cell lines produced resistance to cetuximab and panitumumab by sustaining MAPK phosphorylation. HER2 mutations are potently inhibited by low nanomolar doses of the irreversible tyrosine kinase inhibitors, neratinib and afatinib. HER2 gene sequencing of 48 cetuximab resistant, quadruple (KRAS, NRAS, BRAF, and PIK3CA) WT colorectal cancer patient-derived xenografts (PDX’s) identified 4 PDX’s with HER2 mutations. HER2 targeted therapies were tested on two PDX’s. Treatment with a single HER2 targeted drug (trastuzumab, neratinib, or lapatinib) delayed tumor growth, but dual HER2 targeted therapy with trastuzumab plus tyrosine kinase inhibitors produced regression of these HER2 mutated PDX’s. PMID:26243863

  19. Development of AN Active 238UF6 Gas Target

    NASA Astrophysics Data System (ADS)

    Eckardt, C.; Enders, J.; Freudenberger, M.; Göök, A.; von Neumann-Cosel, P.; Oberstedt, A.; Oberstedt, S.

    2014-09-01

    Detailed studies of the fission process, e.g., the search for parity nonconservation (PNC) effects, the energy dependence of fission modes or the population of fission isomers, depend on high quality data, therefore requiring high luminosities. An active gas target containing uranium may overcome the deterioration of energy and angular resolution caused by large solid target thicknesses. A single Frisch-grid ionization chamber has been built to test a mixture of standard counting gases (e.g., argon) with depleted uranium hexafluoride (238UF6), utilizing a triple alpha source to evaluate signal quality and drift velocity. For mass fractions of up to 4 percent of 238U the drift velocity increases with rising UF6 content, while a good signal quality and energy resolution is preserved.

  20. Haem-activated promiscuous targeting of artemisinin in Plasmodium falciparum.

    PubMed

    Wang, Jigang; Zhang, Chong-Jing; Chia, Wan Ni; Loh, Cheryl C Y; Li, Zhengjun; Lee, Yew Mun; He, Yingke; Yuan, Li-Xia; Lim, Teck Kwang; Liu, Min; Liew, Chin Xia; Lee, Yan Quan; Zhang, Jianbin; Lu, Nianci; Lim, Chwee Teck; Hua, Zi-Chun; Liu, Bin; Shen, Han-Ming; Tan, Kevin S W; Lin, Qingsong

    2015-01-01

    The mechanism of action of artemisinin and its derivatives, the most potent of the anti-malarial drugs, is not completely understood. Here we present an unbiased chemical proteomics analysis to directly explore this mechanism in Plasmodium falciparum. We use an alkyne-tagged artemisinin analogue coupled with biotin to identify 124 artemisinin covalent binding protein targets, many of which are involved in the essential biological processes of the parasite. Such a broad targeting spectrum disrupts the biochemical landscape of the parasite and causes its death. Furthermore, using alkyne-tagged artemisinin coupled with a fluorescent dye to monitor protein binding, we show that haem, rather than free ferrous iron, is predominantly responsible for artemisinin activation. The haem derives primarily from the parasite's haem biosynthesis pathway at the early ring stage and from haemoglobin digestion at the latter stages. Our results support a unifying model to explain the action and specificity of artemisinin in parasite killing. PMID:26694030

  1. Haem-activated promiscuous targeting of artemisinin in Plasmodium falciparum

    PubMed Central

    Wang, Jigang; Zhang, Chong-Jing; Chia, Wan Ni; Loh, Cheryl C. Y.; Li, Zhengjun; Lee, Yew Mun; He, Yingke; Yuan, Li-Xia; Lim, Teck Kwang; Liu, Min; Liew, Chin Xia; Lee, Yan Quan; Zhang, Jianbin; Lu, Nianci; Lim, Chwee Teck; Hua, Zi-Chun; Liu, Bin; Shen, Han-Ming; Tan, Kevin S. W.; Lin, Qingsong

    2015-01-01

    The mechanism of action of artemisinin and its derivatives, the most potent of the anti-malarial drugs, is not completely understood. Here we present an unbiased chemical proteomics analysis to directly explore this mechanism in Plasmodium falciparum. We use an alkyne-tagged artemisinin analogue coupled with biotin to identify 124 artemisinin covalent binding protein targets, many of which are involved in the essential biological processes of the parasite. Such a broad targeting spectrum disrupts the biochemical landscape of the parasite and causes its death. Furthermore, using alkyne-tagged artemisinin coupled with a fluorescent dye to monitor protein binding, we show that haem, rather than free ferrous iron, is predominantly responsible for artemisinin activation. The haem derives primarily from the parasite's haem biosynthesis pathway at the early ring stage and from haemoglobin digestion at the latter stages. Our results support a unifying model to explain the action and specificity of artemisinin in parasite killing. PMID:26694030

  2. Modeling the target acquisition performance of active imaging systems.

    PubMed

    Espinola, Richard L; Jacobs, Eddie L; Halford, Carl E; Vollmerhausen, Richard; Tofsted, David H

    2007-04-01

    Recent development of active imaging system technology in the defense and security community have driven the need for a theoretical understanding of its operation and performance in military applications such as target acquisition. In this paper, the modeling of active imaging systems, developed at the U.S. Army RDECOM CERDEC Night Vision & Electronic Sensors Directorate, is presented with particular emphasis on the impact of coherent effects such as speckle and atmospheric scintillation. Experimental results from human perception tests are in good agreement with the model results, validating the modeling of coherent effects as additional noise sources. Example trade studies on the design of a conceptual active imaging system to mitigate deleterious coherent effects are shown. PMID:19532626

  3. Modeling the target acquisition performance of active imaging systems

    NASA Astrophysics Data System (ADS)

    Espinola, Richard L.; Jacobs, Eddie L.; Halford, Carl E.; Vollmerhausen, Richard; Tofsted, David H.

    2007-04-01

    Recent development of active imaging system technology in the defense and security community have driven the need for a theoretical understanding of its operation and performance in military applications such as target acquisition. In this paper, the modeling of active imaging systems, developed at the U.S. Army RDECOM CERDEC Night Vision & Electronic Sensors Directorate, is presented with particular emphasis on the impact of coherent effects such as speckle and atmospheric scintillation. Experimental results from human perception tests are in good agreement with the model results, validating the modeling of coherent effects as additional noise sources. Example trade studies on the design of a conceptual active imaging system to mitigate deleterious coherent effects are shown.

  4. Calcium-Activated Potassium Channels: Potential Target for Cardiovascular Diseases.

    PubMed

    Dong, De-Li; Bai, Yun-Long; Cai, Ben-Zhi

    2016-01-01

    Ca(2+)-activated K(+) channels (KCa) are classified into three subtypes: big conductance (BKCa), intermediate conductance (IKCa), and small conductance (SKCa) KCa channels. The three types of KCa channels have distinct physiological or pathological functions in cardiovascular system. BKCa channels are mainly expressed in vascular smooth muscle cells (VSMCs) and inner mitochondrial membrane of cardiomyocytes, activation of BKCa channels in these locations results in vasodilation and cardioprotection against cardiac ischemia. IKCa channels are expressed in VSMCs, endothelial cells, and cardiac fibroblasts and involved in vascular smooth muscle proliferation, migration, vessel dilation, and cardiac fibrosis. SKCa channels are widely expressed in nervous and cardiovascular system, and activation of SKCa channels mainly contributes membrane hyperpolarization. In this chapter, we summarize the physiological and pathological roles of the three types of KCa channels in cardiovascular system and put forward the possibility of KCa channels as potential target for cardiovascular diseases. PMID:27038376

  5. Selective inhibition of BET bromodomain epigenetic signalling interferes with the bone-associated tumour vicious cycle.

    PubMed

    Lamoureux, François; Baud'huin, Marc; Rodriguez Calleja, Lidia; Jacques, Camille; Berreur, Martine; Rédini, Françoise; Lecanda, Fernando; Bradner, James E; Heymann, Dominique; Ory, Benjamin

    2014-01-01

    The vicious cycle established between bone-associated tumours and bone resorption is the central problem with therapeutic strategies against primary bone tumours and bone metastasis. Here we report data to support inhibition of BET bromodomain proteins as a promising therapeutic strategy that target simultaneously the three partners of the vicious cycle. Treatment with JQ1, a BET bromodomain inhibitor, reduces cell viability of osteosarcoma cells and inhibits osteoblastic differentiation both in vitro and in vivo. These effects are associated with transcriptional silencing of MYC and RUNX2, resulting from the depletion of BRD4 from their respective loci. Moreover, JQ1 also inhibits osteoclast differentiation by interfering with BRD4-dependent RANKL activation of NFATC1 transcription. Collectively, our data indicate that JQ1 is a potent inhibitor of osteoblast and osteoclast differentiation as well as bone tumour development. PMID:24646477

  6. Phase I/II Clinical Trial of Encapsulated, Cytochrome P450 Expressing Cells as Local Activators of Cyclophosphamide to Treat Spontaneous Canine Tumours

    PubMed Central

    Michałowska, Monika; Winiarczyk, Stanislaw; Adaszek, Łukasz; Łopuszyński, Wojciech; Grądzki, Zbigniew; Salmons, Brian; Günzburg, Walter H.

    2014-01-01

    Based upon promising preclinical studies, a clinical trial was performed in which encapsulated cells overexpressing cytochrome P450 enzyme isoform 2B1 were implanted around malignant mammary tumours arising spontaneously in dogs. The dogs were then given cyclophosphamide, one of the standard chemotherapeutic agents used for the treatment of mammary tumours. The dogs were assessed for a number of clinical parameters as well as for reduction in tumour size. The treatment was well tolerated with no evidence of adverse reactions or side effects being associated with the administration of the encapsulated cells. Reductions in tumour size of more than 50% were observed for 6 out of the 11 tumours analysed while 5 tumours showing minor responses, i.e. stable disease. In contrast, the tumours that received cyclophosphamide alone showed only stable disease. Taken together, this data suggests that encapsulated cytochrome P450 expressing cells combined with chemotherapy may be useful in the local treatment of a number of dog mammary tumours and support the performance of further clinical studies to evaluate this new treatment. PMID:25028963

  7. Overexpression of HER-2 in MDA-MB-435/LCC6 Tumours is Associated with Higher Metabolic Activity and Lower Energy Stress.

    PubMed

    Dragowska, Wieslawa H; Ginj, Mihaela; Kozlowski, Piotr; Yung, Andrew; Ruth, Thomas J; Adam, Michael J; Sossi, Vesna; Bally, Marcel B; Yapp, Donald T T

    2016-01-01

    Overexpresssion of HER-2 in the MDA-MB-435/LCC6 (LCC6(HER-2)) tumour model is associated with significantly increased hypoxia and reduced necrosis compared to isogenic control tumours (LCC6(Vector)); this difference was not related to tumour size or changes in vascular architecture. To further evaluate factors responsible for HER-2-associated changes in the tumour microenvironment, small animal magnetic resonance imaging (MRI) and positron emission tomography (PET) were used to measure tumour tissue perfusion and metabolism, respectively. The imaging data was further corroborated by analysis of molecular markers pertaining to energy homeostasis, and measurements of hypoxia and glucose consumption. The results showed a strong trend towards higher perfusion rates (~58% greater, p = 0.14), and significantly higher glucose uptake in LCC6(HER-2) (~2-fold greater; p = 0.025), relative to control tumours. The expression of proteins related to energy stress (P-AMPK, P-ACC) and glucose transporters (GLUT1) were lower in LCC6(HER-2) tumours (~2- and ~4-fold, respectively). The in vitro analysis showed that LCC6(HER-2) cells become more hypoxic in 1% oxygen and utilise significantly more glucose in normoxia compared to LCC6(Vector)cells (p < 0.005). Amalgamation of all the data points suggests a novel metabolic adaptation driven by HER-2 overexpression where higher oxygen and glucose metabolic rates produce rich energy supply but also a more hypoxic tumour mass. PMID:26727049

  8. Combined inhibition of MAP kinase and KIT signaling synergistically destabilizes ETV1 and suppresses GIST tumour growth

    PubMed Central

    Ran, Leili; Sirota, Inna; Cao, Zhen; Murphy, Devan; Chen, Yuedan; Shukla, Shipra; Xie, Yuanyuan; Kaufmann, Michael C.; Gao, Dong; Zhu, Sinan; Rossi, Ferdinando; Wongvipat, John; Taguchi, Takahiro; Tap, William D.; Mellinghoff, Ingo K.; Besmer, Peter; Antonescu, Cristina R.; Chen, Yu; Chi, Ping

    2015-01-01

    Gastrointestinal stromal tumour (GIST), originating from the interstitial cells of Cajal (ICCs), is characterized by frequent activating mutations of the KIT receptor tyrosine kinase. Despite the clinical success of imatinib that targets KIT, most advanced GIST patients develop resistance and eventually die of the disease. The ETS family transcription factor, ETV1, is a master regulator of the ICC lineage. Using mouse models of Kit activation and Etv1 ablation, we demonstrate that Etv1 is required for GIST initiation and proliferation in vivo, validating it as a therapeutic target. We further uncover a positive feedback circuit where MAP kinase activation downstream of KIT stabilizes the ETV1 protein and ETV1 positively regulates KIT expression. Combined targeting of ETV1 stability by imatinib and MEK162 resulted in increased growth suppression in vitro and complete tumour regression in vivo. The combination strategy to target ETV1 may provide an effective therapeutic strategy in GIST clinical management. PMID:25572173

  9. Hypoxia signalling in cancer and approaches to enforce tumour regression

    NASA Astrophysics Data System (ADS)

    Pouysségur, Jacques; Dayan, Frédéric; Mazure, Nathalie M.

    2006-05-01

    Tumour cells emerge as a result of genetic alteration of signal circuitries promoting cell growth and survival, whereas their expansion relies on nutrient supply. Oxygen limitation is central in controlling neovascularization, glucose metabolism, survival and tumour spread. This pleiotropic action is orchestrated by hypoxia-inducible factor (HIF), which is a master transcriptional factor in nutrient stress signalling. Understanding the role of HIF in intracellular pH (pHi) regulation, metabolism, cell invasion, autophagy and cell death is crucial for developing novel anticancer therapies. There are new approaches to enforce necrotic cell death and tumour regression by targeting tumour metabolism and pHi-control systems.

  10. A Deterministic Approach to Active Debris Removal Target Selection

    NASA Astrophysics Data System (ADS)

    Lidtke, A.; Lewis, H.; Armellin, R.

    2014-09-01

    Many decisions, with widespread economic, political and legal consequences, are being considered based on space debris simulations that show that Active Debris Removal (ADR) may be necessary as the concerns about the sustainability of spaceflight are increasing. The debris environment predictions are based on low-accuracy ephemerides and propagators. This raises doubts about the accuracy of those prognoses themselves but also the potential ADR target-lists that are produced. Target selection is considered highly important as removal of many objects will increase the overall mission cost. Selecting the most-likely candidates as soon as possible would be desirable as it would enable accurate mission design and allow thorough evaluation of in-orbit validations, which are likely to occur in the near-future, before any large investments are made and implementations realized. One of the primary factors that should be used in ADR target selection is the accumulated collision probability of every object. A conjunction detection algorithm, based on the smart sieve method, has been developed. Another algorithm is then applied to the found conjunctions to compute the maximum and true probabilities of collisions taking place. The entire framework has been verified against the Conjunction Analysis Tools in AGIs Systems Toolkit and relative probability error smaller than 1.5% has been achieved in the final maximum collision probability. Two target-lists are produced based on the ranking of the objects according to the probability they will take part in any collision over the simulated time window. These probabilities are computed using the maximum probability approach, that is time-invariant, and estimates of the true collision probability that were computed with covariance information. The top-priority targets are compared, and the impacts of the data accuracy and its decay are highlighted. General conclusions regarding the importance of Space Surveillance and Tracking for the

  11. Improved drug targeting of cancer cells by utilizing actively targetable folic acid-conjugated albumin nanospheres.

    PubMed

    Shen, Zheyu; Li, Yan; Kohama, Kazuhiro; Oneill, Brian; Bi, Jingxiu

    2011-01-01

    Folic acid-conjugated albumin nanospheres (FA-AN) have been developed to provide an actively targetable drug delivery system for improved drug targeting of cancer cells with reduced side effects. The nanospheres were prepared by conjugating folic acid onto the surface of albumin nanospheres using 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDAC) as a catalyst. To test the efficacy of these nanospheres as a potential delivery platform, doxorubicin-loaded albumin nanospheres (DOX-AN) and doxorubicin-loaded FA-AN (FA-DOX-AN) were prepared by entrapping DOX (an anthracycline, antibiotic drug widely used in cancer chemotherapy that works by intercalating DNA) into AN and FA-AN nanoparticles. Cell uptake of the DOX was then measured. The results show that FA-AN was incorporated into HeLa cells (tumor cells) only after 2.0h incubation, whereas HeLa cells failed to incorporate albumin nanospheres without conjugated folic acid after 4.0h incubation. When HeLa cells were treated with the DOX-AN, FA-DOX-AN nanoparticles or free DOX, cell viability decreased with increasing culture time (i.e. cell death increases with time) over a 70h period. Cell viability was always the lowest for free DOX followed by FA-DOX-AN4 and then DOX-AN. In a second set of experiments, HeLa cells washed to remove excess DOX after an initial incubation for 2h were incubated for 70h. The corresponding cell viability was slightly higher when the cells were treated with FA-DOX-AN or free DOX whilst cells treated with DOX-AN nanoparticles remained viable. The above experiments were repeated for non-cancerous, aortic smooth muscle cells (AoSMC). As expected, cell viability of the HeLa cells (with FA receptor alpha, FRα) and AoSMC cells (without FRα) decreased rapidly with time in the presence of free DOX, but treatment with FA-DOX-AN resulted in selective killing of the tumor cells. These results indicated that FA-AN may be used as a promising actively targetable drug delivery system to improve drug

  12. Classification of a frameshift/extended and a stop mutation in WT1 as gain-of-function mutations that activate cell cycle genes and promote Wilms tumour cell proliferation

    PubMed Central

    Busch, Maike; Schwindt, Heinrich; Brandt, Artur; Beier, Manfred; Görldt, Nicole; Romaniuk, Paul; Toska, Eneda; Roberts, Stefan; Royer, Hans-Dieter; Royer-Pokora, Brigitte

    2014-01-01

    The WT1 gene encodes a zinc finger transcription factor important for normal kidney development. WT1 is a suppressor for Wilms tumour development and an oncogene for diverse malignant tumours. We recently established cell lines from primary Wilms tumours with different WT1 mutations. To investigate the function of mutant WT1 proteins, we performed WT1 knockdown experiments in cell lines with a frameshift/extension (p.V432fsX87 = Wilms3) and a stop mutation (p.P362X = Wilms2) of WT1, followed by genome-wide gene expression analysis. We also expressed wild-type and mutant WT1 proteins in human mesenchymal stem cells and established gene expression profiles. A detailed analysis of gene expression data enabled us to classify the WT1 mutations as gain-of-function mutations. The mutant WT1Wilms2 and WT1Wilms3 proteins acquired an ability to modulate the expression of a highly significant number of genes from the G2/M phase of the cell cycle, and WT1 knockdown experiments showed that they are required for Wilms tumour cell proliferation. p53 negatively regulates the activity of a large number of these genes that are also part of a core proliferation cluster in diverse human cancers. Our data strongly suggest that mutant WT1 proteins facilitate expression of these cell cycle genes by antagonizing transcriptional repression mediated by p53. We show that mutant WT1 can physically interact with p53. Together the findings show for the first time that mutant WT1 proteins have a gain-of-function and act as oncogenes for Wilms tumour development by regulating Wilms tumour cell proliferation. PMID:24619359

  13. Role of ascorbate in the activation of NF-kappaB by tumour necrosis factor-alpha in T-cells.

    PubMed Central

    Muñoz, E; Blázquez, M V; Ortiz, C; Gomez-Díaz, C; Navas, P

    1997-01-01

    The first product of ascorbate oxidation, the ascorbate free radical (AFR), acts in biological systems mainly as an oxidant, and through its role in the plasma membrane redox system exerts different effects on the cell. We have investigated the role of ascorbate, AFR and dehydroascorbate (DHA) in the activation of the NF-kappaB transcription factor in Jurkat T-cells stimulated by tumour necrosis factor-alpha (TNF-alpha). Here we show, by electrophoretic mobility shift assays, that ascorbate increases the binding of NF-kappaB to DNA in TNF-alpha-stimulated Jurkat cells. The ability of ascorbate to enhance cytoplasmic inhibitory IkBalpha protein degradation correlates completely with its capacity to induce NF-kappaB binding to DNA and to potentiate NF-kappaB-mediated transactivation of the HIV-1 long terminal repeat promoter in TNF-alpha-stimulated Jurkat cells but not in cells stimulated with PMA plus ionomycin. AFR behaves like ascorbate, while DHA and ascorbate phosphate do not affect TNF-alpha-mediated NF-kappaB activation. These results provide new evidence for a possible relationship between the activation of the electron-transport system at the plasma membrane by ascorbate or its free radical and redox-dependent gene transcription in T-cells. PMID:9224625

  14. Active imaging system performance model for target acquisition

    NASA Astrophysics Data System (ADS)

    Espinola, Richard L.; Teaney, Brian; Nguyen, Quang; Jacobs, Eddie L.; Halford, Carl E.; Tofsted, David H.

    2007-04-01

    The U.S. Army RDECOM CERDEC Night Vision & Electronic Sensors Directorate has developed a laser-range-gated imaging system performance model for the detection, recognition, and identification of vehicle targets. The model is based on the established US Army RDECOM CERDEC NVESD sensor performance models of the human system response through an imaging system. The Java-based model, called NVLRG, accounts for the effect of active illumination, atmospheric attenuation, and turbulence effects relevant to LRG imagers, such as speckle and scintillation, and for the critical sensor and display components. This model can be used to assess the performance of recently proposed active SWIR systems through various trade studies. This paper will describe the NVLRG model in detail, discuss the validation of recent model components, present initial trade study results, and outline plans to validate and calibrate the end-to-end model with field data through human perception testing.

  15. Novel strategies for ultrahigh specific activity targeted nanoparticles

    SciTech Connect

    Zhou, Dong

    2012-12-13

    We have developed novel strategies optimized for preparing high specific activity radiolabeled nanoparticles, targeting nuclear imaging of low abundance biomarkers. Several compounds have been labeled with F-18 and Cu-64 for radiolabeling of SCK-nanoparticles via Copper(I) catalyzed or copper-free alkyne-azide cyclolization. Novel strategies have been developed to achieve ultrahigh specific activity with administrable amount of dose for human study using copper-free chemistry. Ligands for carbonic anhydrase 12 (CA12), a low abundance extracellular biomarker for the responsiveness of breast cancer to endocrine therapie, have been labeled with F-18 and Cu-64, and one of them has been evaluated in animal models. The results of this project will lead to major improvements in the use of nanoparticles in nuclear imaging and will significantly advance their potential for detecting low abundance biomarkers of medical importance.

  16. Small Molecule Inhibitors Targeting Activator Protein 1 (AP-1)

    PubMed Central

    2015-01-01

    Activator protein 1 (AP-1) is a pivotal transcription factor that regulates a wide range of cellular processes including proliferation, apoptosis, differentiation, survival, cell migration, and transformation. Accumulating evidence supports that AP-1 plays an important role in several severe disorders including cancer, fibrosis, and organ injury, as well as inflammatory disorders such as asthma, psoriasis, and rheumatoid arthritis. AP-1 has emerged as an actively pursued drug discovery target over the past decade. Excitingly, a selective AP-1 inhibitor T-5224 (51) has been investigated in phase II human clinical trials. Nevertheless, no effective AP-1 inhibitors have yet been approved for clinical use. Despite significant advances achieved in understanding AP-1 biology and function, as well as the identification of small molecules modulating AP-1 associated signaling pathways, medicinal chemistry efforts remain an urgent need to yield selective and efficacious AP-1 inhibitors as a viable therapeutic strategy for human diseases. PMID:24831826

  17. Targeted training modifies oscillatory brain activity in schizophrenia patients

    PubMed Central

    Popov, Tzvetan G.; Carolus, Almut; Schubring, David; Popova, Petia; Miller, Gregory A.; Rockstroh, Brigitte S.

    2015-01-01

    Effects of both domain-specific and broader cognitive remediation protocols have been reported for neural activity and overt performance in schizophrenia (SZ). Progress is limited by insufficient knowledge of relevant neural mechanisms. Addressing neuronal signal resolution in the auditory system as a mechanism contributing to cognitive function and dysfunction in schizophrenia, the present study compared effects of two neuroplasticity-based training protocols targeting auditory–verbal or facial affect discrimination accuracy and a standard rehabilitation protocol on magnetoencephalographic (MEG) oscillatory brain activity in an auditory paired-click task. SZ were randomly assigned to either 20 daily 1-hour sessions over 4 weeks of auditory–verbal training (N = 19), similarly intense facial affect discrimination training (N = 19), or 4 weeks of treatment as usual (TAU, N = 19). Pre-training, the 57 SZ showed smaller click-induced posterior alpha power modulation than did 28 healthy comparison participants, replicating Popov et al. (2011b). Abnormally small alpha decrease 300–800 ms around S2 improved more after targeted auditory–verbal training than after facial affect training or TAU. The improvement in oscillatory brain dynamics with training correlated with improvement on a measure of verbal learning. Results replicate previously reported effects of neuroplasticity-based psychological training on oscillatory correlates of auditory stimulus differentiation, encoding, and updating and indicate specificity of cortical training effects. PMID:26082889

  18. Identification of genes involved in the biology of atypical teratoid/rhabdoid tumours using Drosophila melanogaster.

    PubMed

    Jeibmann, Astrid; Eikmeier, Kristin; Linge, Anna; Kool, Marcel; Koos, Björn; Schulz, Jacqueline; Albrecht, Stefanie; Bartelheim, Kerstin; Frühwald, Michael C; Pfister, Stefan M; Paulus, Werner; Hasselblatt, Martin

    2014-01-01

    Atypical teratoid/rhabdoid tumours (AT/RT) are malignant brain tumours. Unlike most other human brain tumours, AT/RT are characterized by inactivation of one single gene, SMARCB1. SMARCB1 is a member of the evolutionarily conserved SWI/SNF chromatin remodelling complex, which has an important role in the control of cell differentiation and proliferation. Little is known, however, about the pathways involved in the oncogenic effects of SMARCB1 inactivation, which might also represent targets for treatment. Here we report a comprehensive genetic screen in the fruit fly that revealed several genes not yet associated with loss of snr1, the Drosophila homologue of SMARCB1. We confirm the functional role of identified genes (including merlin, kibra and expanded, known to regulate hippo signalling pathway activity) in human rhabdoid tumour cell lines and AT/RT tumour samples. These results demonstrate that fly models can be employed for the identification of clinically relevant pathways in human cancer. PMID:24892285

  19. Transport processes in tumours.

    PubMed

    Quastel, J H

    1965-12-01

    The characteristic features of transport systems controlling influx into tumour cells of nutrients and other chemicals are briefly described. Two notable features of transport of amino acids into tumour cells have been observed: extensive accumulation against a concentration gradient and equal accumulations, whether conditions are aerobic or anaerobic, provided glucose is present. This combination of features has not been observed in the majority of normal mammalian tissues so far examined. Important for considerations of chemotherapy is the ability of tumour transport carriers to transfer substances related in structure to amino acids and other nutrients. Amino acid analogues, for example, can either block transport of natural amino acids or can be transported into the cell where they may interfere with various aspects of amino acid metabolism. The study of transport carriers is essential for an understanding of tumour-host relationships and for considerations of chemotherapy. PMID:5842595

  20. Second-Line Treatment of Non-Small Cell Lung Cancer: New Developments for Tumours Not Harbouring Targetable Oncogenic Driver Mutations.

    PubMed

    Barnfield, Paul C; Ellis, Peter M

    2016-09-01

    Platinum-based doublet chemotherapy with or without bevacizumab is the standard of care for the initial management of advanced and metastatic non-small cell lung cancer (NSCLC) without a targetable molecular abnormality. However, the majority of patients with NSCLC will ultimately develop resistance to initial platinum-based chemotherapy, and many remain candidates for subsequent lines of therapy. Randomised trials over the past 10-15 years have established pemetrexed (non-squamous histology), docetaxel, erlotinib and gefitinib as approved second-line agents in NSCLC without targetable driver mutations or rearrangements. Trials comparing these agents with other chemotherapy, evaluating the addition of an epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) to chemotherapy or the addition of another targeted agent to erlotinib or gefitinib have all failed to demonstrate an improvement in overall survival for patients with NSCLC. In contrast, recent data comparing therapy with novel monoclonal antibodies against programmed cell death 1 (PD-1) or PD ligand (PD-L1) pathway versus standard chemotherapy following platinum failure have demonstrated significant improvements in overall survival. Therapy with nivolumab or pembrolizumab would now be considered standard second-line therapy in patients without contraindication to immune checkpoint inhibitors. Atezolizumab also appears promising in this setting. PMID:27557830

  1. Cancer Cell Death-Inducing Radiotherapy: Impact on Local Tumour Control, Tumour Cell Proliferation and Induction of Systemic Anti-tumour Immunity.

    PubMed

    Frey, Benjamin; Derer, Anja; Scheithauer, Heike; Wunderlich, Roland; Fietkau, Rainer; Gaipl, Udo S

    2016-01-01

    Radiotherapy (RT) predominantly is aimed to induce DNA damage in tumour cells that results in reduction of their clonogenicity and finally in tumour cell death. Adaptation of RT with higher single doses has become necessary and led to a more detailed view on what kind of tumour cell death is induced and which immunological consequences result from it. RT is capable of rendering tumour cells immunogenic by modifying the tumour cell phenotype and the microenvironment. Danger signals are released as well as the senescence-associated secretory phenotype. This results in maturation of dendritic cells and priming of cytotoxic T cells as well as in activation of natural killer cells. However, RT on the other hand can also result in immune suppressive events including apoptosis induction and foster tumour cell proliferation. That's why RT is nowadays increasingly combined with selected immunotherapies. PMID:27558821

  2. Differential partial activation phenotype and production of tumour necrosis factor-α by conventional dendritic cells in response to lipopolysaccharide in HIV+ viraemic subjects and HIV+ controllers

    PubMed Central

    Camacho-Sandoval, R; Del Río Estrada, P M; Rivero-Arrieta, A; Reyes-Terán, G; Bonifaz, L C

    2014-01-01

    HIV+ subjects are reported to have increased soluble CD14 (sCD14) in plasma, an indicator of microbial translocation. We evaluated if microbial translocation has a differential impact on the activation and function of conventional dendritic cells (cDC) from viraemic HIV+ subjects and HIV+ controllers (CTs). The HIV+ subjects were classified into two groups according to their plasma viral load (pVL): CT and viraemic. Subjects without HIV were included as controls (HIV–). The frequencies and phenotypes of cDC from these subjects were evaluated by multi-parameter flow cytometry. In addition, peripheral blood mononuclear cells (PBMCs) were stimulated with lipopolysaccharide (LPS) or single-stranded RNA40 (ssRNA40), the phenotype of the cDC and the intracellular production of tumour necrosis factor (TNF)-α by the cDC were evaluated by flow cytometry. We observed a partial activation phenotype for the cDC in the viraemic subjects and CTs ex vivo and after LPS activation, which showed differences in the expression of CD40 and CD86. Furthermore, in response to LPS the cDC from the viraemic subjects produced more TNF-α compared to the cDC from CTs. Interestingly, the percentage of TNF-α+ cDC was found to be correlated positively with the pVL. The partial activation of cDC and the over-production of TNF-α in response to LPS in viraemic HIV+ subjects might be related to the increased chronic activation observed in these subjects. In contrast, cDC from CTs seem to have a regulated response to LPS, indicating that they respond differently to chronic immune activation. These results may have implications in the development of HIV therapies and vaccines using DC. PMID:25130456

  3. Breast tumour angiogenesis

    PubMed Central

    Fox, Stephen B; Generali, Daniele G; Harris, Adrian L

    2007-01-01

    The central importance of tumour neovascularization has been emphasized by clinical trials using antiangiogenic therapy in breast cancer. This review gives a background to breast tumour neovascularization in in situ and invasive breast cancer, outlines the mechanisms by which this is achieved and discusses the influence of the microenvironment, focusing on hypoxia. The regulation of angiogenesis and the antivascular agents that are used in an antiangiogenic dosing schedule, both novel and conventional, are also summarized. PMID:18190723

  4. [Tumours and liver transplants].

    PubMed

    Mejzlík, Vladimír; Husová, Libuše; Kuman, Milan; Štěpánková, Soňa; Ondrášek, Jiří; Němec, Petr

    2015-01-01

    Liver transplantation as a curative treatment method can be used for selected primary liver tumours, in particular for hepatocellular carcinoma and rather rare semi-malignant tumours such as epithelioid hemangioendothelioma, further for infiltration of liver by metastatic neuroendocrine tumours (provided that metastases are only located in the liver and the primary tumour was removed) and for benign tumours (hemangiomas and adenomas) with oppression symptoms and size progression. Cholangiocarcinoma is not indicated for liver transplantation at the CKTCH Brno. In recent years liver transplants for hepatocellular carcinoma have increased and hepatocellular carcinoma has also been more frequently found ex post, in the explanted livers. Liver transplantation is indicated in selected patients with a good chance of long-term survival after liver transplantation (a generally accepted limit is 5 year survival of 50 % after transplantation). By 20 March 2015 there were liver transplants carried out on 38 patients - in 25 of them was hepatocellular carcinoma diagnosed before transplantation and in 13 it was found in the liver explants. 5 year survival following transplantation is reached by 53 % of this cohort. 32 % patients suffered from chronic hepatitis C. The longest surviving (32 years) patient at CKTCH Brno had liver transplanted for a big fibrolamellar hepatocellular carcinoma, which points to the prognostic significance of tumour histology: the criterion only considered in some indication schemes for practical reasons. Benign liver tumours (adenomatosis, cystadenoma, hemangioma with oppression symptoms) are rather rare indications and the transplantation results are favourable. 4 patients underwent transplantation for infiltration of liver by carcinoid, tumour recurrence occurred in one. PMID:26375706

  5. Local tumour hyperthermia as immunotherapy for metastatic cancer

    PubMed Central

    Toraya-Brown, Seiko; Fiering, Steven

    2014-01-01

    Abstract Local tumour hyperthermia for cancer treatment is currently used either for ablation purposes as an alternative to surgery or less frequently, in combination with chemotherapy and/or radiation therapy to enhance the effects of those traditional therapies. As it has become apparent that activating the immune system is crucial to successfully treat metastatic cancer, the potential of boosting anti-tumour immunity by heating tumours has become a growing area of cancer research. After reviewing the history of hyperthermia therapy for cancer and introducing methods for inducing local hyperthermia, this review describes different mechanisms by which heating tumours can elicit anti-tumour immune responses, including tumour cell damage, tumour surface molecule changes, heat shock proteins, exosomes, direct effects on immune cells, and changes in the tumour vasculature. We then go over in vivo studies that provide promising results showing that local hyperthermia therapy indeed activates various systemic anti-tumour immune responses that slow growth of untreated tumours. Finally, future research questions that will help bring the use of local hyperthermia as systemic immunotherapy closer to clinical application are discussed. PMID:25430985

  6. Defining the clonal dynamics leading to mouse skin tumour initiation.

    PubMed

    Sánchez-Danés, Adriana; Hannezo, Edouard; Larsimont, Jean-Christophe; Liagre, Mélanie; Youssef, Khalil Kass; Simons, Benjamin D; Blanpain, Cédric

    2016-08-18

    The changes in cell dynamics after oncogenic mutation that lead to the development of tumours are currently unknown. Here, using skin epidermis as a model, we assessed the effect of oncogenic hedgehog signalling in distinct cell populations and their capacity to induce basal cell carcinoma, the most frequent cancer in humans. We found that only stem cells, and not progenitors, initiated tumour formation upon oncogenic hedgehog signalling. This difference was due to the hierarchical organization of tumour growth in oncogene-targeted stem cells, characterized by an increase in symmetric self-renewing divisions and a higher p53-dependent resistance to apoptosis, leading to rapid clonal expansion and progression into invasive tumours. Our work reveals that the capacity of oncogene-targeted cells to induce tumour formation is dependent not only on their long-term survival and expansion, but also on the specific clonal dynamics of the cancer cell of origin. PMID:27459053

  7. The ratio of maximum percent tumour accumulations of the pretargeting agent and the radiolabelled effector is independent of tumour size.

    PubMed

    Liu, Guozheng; Dou, Shuping; Liang, Minmin; Chen, Xiangji; Rusckowski, Mary; Hnatowich, Donald J

    2009-11-01

    Our previous studies have indicated that the optimal dosage ratio of pretargeting antibody to effector is proportional to their maximum percent tumour accumulations (MPTAs). This study quantitatively describes how both MPTAs and their ratio change with tumour size, to simplify pretargeting optimisation when tumour size varies. The CC49 antibody dosages below saturation of the tumour antigen level were first examined for the LS174T tumour mouse model. Then the MPTAs of the antibody in mice bearing tumours of different sizes were determined, always at antibody dosages below antigen saturation. Historical data from this laboratory were used to collect the MPTAs of the (99m)Tc-cMORF effector for different tumour sizes, always at effector dosages below that required to saturate the MORF in tumour. The MPTAs versus tumour sizes for both the antibody and the effector were fitted non-linearly. The best fit of the antibody MPTA (Y(antibody)) with tumour size (x) in grams was Y(antibody)=19.00 x(-0.65) while that for the effector was Y(effector)=4.51x(-0.66). Thus, even though the MPTAs of both vary with tumour size, the ratio (Y(antibody)/Y(effector)) is a constant at 4.21. In conclusion, the MPTA ratio of the antibody to the effector was found to be constant with tumour size, an observation that will simplify pretargeting optimisation because remeasurement of the optimum dosage ratio for different tumour sizes can be avoided. Theoretical considerations also suggest that this relationship may be universal for alternative antibody/effector pairs and for different target models, but this must be experimentally confirmed. PMID:19811906

  8. Testicular germ cell tumours.

    PubMed

    Rajpert-De Meyts, Ewa; McGlynn, Katherine A; Okamoto, Keisei; Jewett, Michael A S; Bokemeyer, Carsten

    2016-04-23

    Testicular germ cell tumours are at the crossroads of developmental and neoplastic processes. Their cause has not been fully elucidated but differences in incidences suggest that a combination of genetic and environment factors are involved, with environmental factors predominating early in life. Substantial progress has been made in understanding genetic susceptibility in the past 5 years on the basis of the results of large genome-wide association studies. Testicular germ cell tumours are highly sensitive to radiotherapy and chemotherapy and hence have among the best outcomes of all tumours. Because the tumours occur mainly in young men, preservation of reproductive function, quality of life after treatment, and late effects are crucial concerns. In this Seminar, we provide an overview of advances in the understanding of the epidemiology, genetics, and biology of testicular germ cell tumours. We also summarise the consensus on how to treat testicular germ cell tumours and focus on a few controversies and improvements in the understanding of late effects of treatment and quality of life for survivors. PMID:26651223

  9. The Fn14 cytoplasmic tail binds tumour-necrosis-factor-receptor-associated factors 1, 2, 3 and 5 and mediates nuclear factor-kappaB activation.

    PubMed Central

    Brown, Sharron A N; Richards, Christine M; Hanscom, Heather N; Feng, Sheau-Line Y; Winkles, Jeffrey A

    2003-01-01

    Fn14 is a growth-factor-inducible immediate-early-response gene encoding a 102-amino-acid type I transmembrane protein. The human Fn14 protein was recently identified as a cell-surface receptor for the tumour necrosis factor (TNF) superfamily member named TWEAK (TNF-like weak inducer of apoptosis). In the present paper, we report that the human TWEAK extracellular domain can also bind the murine Fn14 protein. Furthermore, site-specific mutagenesis and directed yeast two-hybrid interaction assays revealed that the TNFR-associated factor (TRAF) 1, 2, 3 and 5 adaptor molecules bind the murine Fn14 cytoplasmic tail at an overlapping, but non-identical, amino acid sequence motif. We also found that TWEAK treatment of quiescent NIH 3T3 cells stimulates inhibitory kappaBalpha phosphorylation and transcriptional activation of a nuclear factor-kappaB (NF-kappaB) enhancer/luciferase reporter construct. Fn14 overexpression in transiently transfected NIH 3T3 cells also promotes NF-kappaB activation, and this cellular response requires an intact TRAF binding site. These results indicate that Fn14 is a functional TWEAK receptor that can associate with four distinct TRAF family members and stimulate the NF-kappaB transcription factor signalling pathway. PMID:12529173

  10. Decoy receptors block TRAIL sensitivity at a supracellular level: the role of stromal cells in controlling tumour TRAIL sensitivity.

    PubMed

    O'Leary, L; van der Sloot, A M; Reis, C R; Deegan, S; Ryan, A E; Dhami, S P S; Murillo, L S; Cool, R H; Correa de Sampaio, P; Thompson, K; Murphy, G; Quax, W J; Serrano, L; Samali, A; Szegezdi, E

    2016-03-10

    Tumour necrosis factor-related apoptosis-inducing ligand (TRAIL) is a death ligand cytokine known for its cytotoxic activity against malignantly transformed cells. TRAIL induces cell death through binding to death receptors DR4 and DR5. The inhibitory decoy receptors (DcR1 and DcR2) co-expressed with death receptor 4 (DR4)/DR5 on the same cell can block the transmission of the apoptotic signal. Here, we show that DcRs also regulate TRAIL sensitivity at a supracellular level and thus represent a mechanism by which the microenvironment can diminish tumour TRAIL sensitivity. Mathematical modelling and layered or spheroid stroma-extracellular matrix-tumour cultures were used to model the tumour microenvironment. By engineering TRAIL to escape binding by DcRs, we found that DcRs do not only act in a cell-autonomous or cis-regulatory manner, but also exert trans-cellular regulation originating from stromal cells and affect tumour cells, highlighting the potent inhibitory effect of DcRs in the tumour tissue and the necessity of selective targeting of the two death-inducing TRAIL receptors to maximise efficacy. PMID:26050621

  11. Suppressed rate of carcinogenesis and decreases in tumour volume and lung metastasis in CXCL14/BRAK transgenic mice.

    PubMed

    Hata, Ryu-Ichiro; Izukuri, Kazuhito; Kato, Yasumasa; Sasaki, Soichiro; Mukaida, Naofumi; Maehata, Yojiro; Miyamoto, Chihiro; Akasaka, Tetsu; Yang, Xiaoyan; Nagashima, Yoji; Takeda, Kazuyoshi; Kiyono, Tohru; Taniguchi, Masaru

    2015-01-01

    Cancer progression involves carcinogenesis, an increase in tumour size, and metastasis. Here, we investigated the effect of overexpressed CXC chemokine ligand 14 (CXCL14) on these processes by using CXCL14/BRAK (CXCL14) transgenic (Tg) mice. The rate of AOM/DSS-induced colorectal carcinogenesis in these mice was significantly lower compared with that for isogenic wild type C57BL/6 (Wt) mice. When tumour cells were injected into these mice, the size of the tumours that developed and the number of metastatic nodules in the lungs of the animals were always significantly lower in the Tg mice than in the Wt ones. Injection of anti-asialo-GM1 antibodies to the mice before and after injection of tumour cells attenuated the suppressing effects of CXCL14 on the tumor growth and metastasis, suggesting that NK cell activity played an important role during CXCL14-mediated suppression of tumour growth and metastasis. The importance of NK cells on the metastasis was also supported when CXCL14 was expressed in B16 melanoma cells. Further, the survival rates after tumour cell injection were significantly increased for the Tg mice. As these Tg mice showed no obvious abnormality, we propose that CXCL14 to be a promising molecular target for cancer suppression/prevention. PMID:25765541

  12. Target-classification approach applied to active UXO sites

    NASA Astrophysics Data System (ADS)

    Shubitidze, F.; Fernández, J. P.; Shamatava, Irma; Barrowes, B. E.; O'Neill, K.

    2013-06-01

    This study is designed to illustrate the discrimination performance at two UXO active sites (Oklahoma's Fort Sill and the Massachusetts Military Reservation) of a set of advanced electromagnetic induction (EMI) inversion/discrimination models which include the orthonormalized volume magnetic source (ONVMS), joint diagonalization (JD), and differential evolution (DE) approaches and whose power and flexibility greatly exceed those of the simple dipole model. The Fort Sill site is highly contaminated by a mix of the following types of munitions: 37-mm target practice tracers, 60-mm illumination mortars, 75-mm and 4.5'' projectiles, 3.5'', 2.36'', and LAAW rockets, antitank mine fuzes with and without hex nuts, practice MK2 and M67 grenades, 2.5'' ballistic windshields, M2A1-mines with/without bases, M19-14 time fuzes, and 40-mm practice grenades with/without cartridges. The site at the MMR site contains targets of yet different sizes. In this work we apply our models to EMI data collected using the MetalMapper (MM) and 2 × 2 TEMTADS sensors. The data for each anomaly are inverted to extract estimates of the extrinsic and intrinsic parameters associated with each buried target. (The latter include the total volume magnetic source or NVMS, which relates to size, shape, and material properties; the former includes location, depth, and orientation). The estimated intrinsic parameters are then used for classification performed via library matching and the use of statistical classification algorithms; this process yielded prioritized dig-lists that were submitted to the Institute for Defense Analyses (IDA) for independent scoring. The models' classification performance is illustrated and assessed based on these independent evaluations.

  13. Development of an Active 238UF6 Gas Target

    NASA Astrophysics Data System (ADS)

    Eckardt, C.; Enders, J.; Freudenberger, M.; Gook, A.; von Neumann-Cosel, P.; Oberstedt, A.; Oberstedt, S.

    At the superconducting 130 MeV Darmstadt electron linac S-DALINAC a new source of spin-polarized electrons using a GaAs cathode has been installed, opening the path for experiments with polarized electron and photon beams for nuclear structure studies at low momentum transfers, e.g., the search for forward-backward asymmetries originating from parity non-conservation (PNC) in the photon-induced fission process of 238U.Detailed studies of different properties, e.g., the energy dependence of fission modes, the population of fission isomers, or the search for (PNC) effects in the photon-induced fission process of 238U, depends on high quality data, therefore needing high luminosities. An active gas target containing uranium may overcome the problem that large solid target thicknesses cause poor energy and angular resolution.A single Frisch-grid ionization chamber has been built to test a mixture of standard counting gases (e.g., argon) with depleted uraniumhexafluoride (238UF6) using a triple alpha source, evaluating signal quality and drift velocity. For mass fractions up to 2 percent of 238U in the counting gas. The drift velocity increases with rising UF6 content, while a good signal quality and energy resolution is preserved.

  14. Azo-reductase activated budesodine prodrugs for colon targeting.

    PubMed

    Marquez Ruiz, Juan F; Kedziora, Kinga; O'Reilly, Mary; Maguire, Jacqueline; Keogh, Brian; Windle, Henry; Kelleher, Dermot P; Gilmer, John F

    2012-12-15

    Budesodine is a synthetic glurocorticoid that undergoes substantial first pass metabolism, limiting systemic exposure. Its use in treatment of inflammatory bowel disease would benefit from a targeting strategy that could lead to a local topical effect, improving safety and increasing anti-inflammatory efficacy. A two-step prodrug strategy involving azoreduction/cyclization that we developed previously for prednisolone is here applied with some variations to budesonide. The budesodine prodrugs were tested using an in vitro azoreductase assay simulating human colonic microflora. The kinetics of amino steroid ester cyclization and its pH dependence was also evaluated. The stability of the prodrugs systems in simulated human duodenal and gastric fluid was evaluated to determine the likelihood of intact intestinal transit. The propionic acid derived prodrug 3 undergoes rapid activation by Clostridium perfingens and its putative reduction product cyclizes with acceptable rapidity when synthesized independently. These properties of 3 suggest that it has potential in management of ulcerative colitis. PMID:23122819

  15. Activating frataxin expression by repeat-targeted nucleic acids

    PubMed Central

    Li, Liande; Matsui, Masayuki; Corey, David R.

    2016-01-01

    Friedreich's ataxia is an incurable genetic disorder caused by a mutant expansion of the trinucleotide GAA within an intronic FXN RNA. This expansion leads to reduced expression of frataxin (FXN) protein and evidence suggests that transcriptional repression is caused by an R-loop that forms between the expanded repeat RNA and complementary genomic DNA. Synthetic agents that increase levels of FXN protein might alleviate the disease. We demonstrate that introducing anti-GAA duplex RNAs or single-stranded locked nucleic acids into patient-derived cells increases FXN protein expression to levels similar to analogous wild-type cells. Our data are significant because synthetic nucleic acids that target GAA repeats can be lead compounds for restoring curative FXN levels. More broadly, our results demonstrate that interfering with R-loop formation can trigger gene activation and reveal a new strategy for upregulating gene expression. PMID:26842135

  16. Computed tomography imaging-guided radiotherapy by targeting upconversion nanocubes with significant imaging and radiosensitization enhancements

    PubMed Central

    Xing, Huaiyong; Zheng, Xiangpeng; Ren, Qingguo; Bu, Wenbo; Ge, Weiqiang; Xiao, Qingfeng; Zhang, Shengjian; Wei, Chenyang; Qu, Haiyun; Wang, Zheng; Hua, Yanqing; Zhou, Liangping; Peng, Weijun; Zhao, Kuaile; Shi, Jianlin

    2013-01-01

    The clinical potentials of radiotherapy could not be achieved completely because of the inaccurate positioning and inherent radioresistance of tumours. In this study, a novel active-targeting upconversion theranostic agent (arginine-glycine-aspartic acid-labelled BaYbF5: 2% Er3+ nanocube) was developed for the first time to address these clinical demands. Heavy metal-based nanocubes (~10 nm) are potential theranostic agents with bifunctional features: computed tomography (CT) contrast agents for targeted tumour imaging and irradiation dose enhancers in tumours during radiotherapy. Remarkably, they showed low toxicity and excellent performance in active-targeting CT imaging and CT imaging-guided radiosensitizing therapy, which could greatly concentrate and enlarge the irradiation dose deposition in tumours to enhance therapeutic efficacy and minimize the damage to surrounding tissues. PMID:23624542

  17. The Prostate Specific Membrane Antigen Regulates the Expression of IL-6 and CCL5 in Prostate Tumour Cells by Activating the MAPK Pathways1

    PubMed Central

    Colombatti, Marco; Fracasso, Giulio; Scupoli, Maria Teresa; Cingarlini, Sara; Poffe, Ornella; Naim, Hassan Y.; Heine, Martin; Tridente, Giuseppe; Mainiero, Fabrizio; Ramarli, Dunia

    2009-01-01

    The interleukin-6 (IL-6) and the chemokine CCL5 are implicated in the development and progression of several forms of tumours including that of the prostate. The expression of the prostate specific membrane antigen (PSMA) is augmented in high-grade and metastatic tumors. Observations of the clinical behaviour of prostate tumors suggest that the increased secretion of IL-6 and CCL5 and the higher expression of PSMA may be correlated. We hypothesized that PSMA could be endowed with signalling properties and that its stimulation might impact on the regulation of the gene expression of IL-6 and CCL5. We herein demonstrate that the cross-linking of cell surface PSMA with specific antibodies activates the small GTPases RAS and RAC1 and the MAPKs p38 and ERK1/2 in prostate carcinoma LNCaP cells. As downstream effects of the PSMA-fostered RAS-RAC1-MAPK pathway activation we observed a strong induction of NF-κB activation associated with an increased expression of IL-6 and CCL5 genes. Pharmacological blockade with specific inhibitors revealed that both p38 and ERK1/2 participate in the phenomenon, although a major role exerted by p38 was evident. Finally we demonstrate that IL-6 and CCL5 enhanced the proliferative potential of LNCaP cells synergistically and in a dose-dependent manner and that CCL5 functioned by receptor-mediated activation of the STAT5-Cyclin D1 pro-proliferative pathway. The novel functions attributable to PSMA which are described in the present report may have profound influence on the survival and proliferation of prostate tumor cells, accounting for the observation that PSMA overexpression in prostate cancer patients is related to a worse prognosis. PMID:19242540

  18. A Natural Small Molecule Harmine Inhibits Angiogenesis and Suppresses Tumour Growth through Activation of p53 in Endothelial Cells

    PubMed Central

    Dai, Fujun; Chen, Yihua; Song, Yajuan; Huang, Li; Zhai, Dong; Dong, Yanmin; Lai, Li; Zhang, Tao; Li, Dali; Pang, Xiufeng; Liu, Mingyao; Yi, Zhengfang

    2012-01-01

    Activation of p53 effectively inhibits tumor angiogenesis that is necessary for tumor growth and metastasis. Reactivation of the p53 by small molecules has emerged as a promising new strategy for cancer therapy. Several classes of small-molecules that activate the p53 pathway have been discovered using various approaches. Here, we identified harmine (β-carboline alkaloid) as a novel activator of p53 signaling involved in inhibition of angiogenesis and tumor growth. Harmine induced p53 phosphorylation and disrupted the p53-MDM2 interaction. Harmine also prevented p53 degradation in the presence of cycloheximide and activated nuclear accumulation of p53 followed by increasing its transcriptional activity in endothelial cells. Moreover, harmine not only induced endothelial cell cycle arrest and apoptosis, but also suppressed endothelial cell migration and tube formation as well as induction of neovascularity in a mouse corneal micropocket assay. Finally, harmine inhibited tumor growth by reducing tumor angiogenesis, as demonstrated by a xenograft tumor model. Our results suggested a novel mechanism and bioactivity of harmine, which inhibited tumor growth by activating the p53 signaling pathway and blocking angiogenesis in endothelial cells. PMID:23300602

  19. A new arylbenzofuran derivative functions as an anti-tumour agent by inducing DNA damage and inhibiting PARP activity

    PubMed Central

    Chen, Hongbo; Zeng, Xiaobin; Gao, Chunmei; Ming, Pinghong; Zhang, Jianping; Guo, Caiping; Zhou, Lanzhen; Lu, Yin; Wang, Lijun; Huang, Laiqiang; He, Xiangjiu; Mei, Lin

    2015-01-01

    We previously reported that 7-hydroxy-5, 4’-dimethoxy-2-arylbenzofuran (HDAB) purified from Livistona chinensis is a key active agent. The present study investigated the function and molecular mechanism of HDAB. HDAB treatment of cervical cancer cells resulted in S phase arrest and apoptosis, together with cyclin A2 and CDK2 upregulation. Cyclin A2 siRNA and a CDK inhibitor efficiently relieved S phase arrest but increased the apoptosis rate. Mechanistic studies revealed that HDAB treatment significantly increased DNA strand breaks in an alkaline comet assay and induced ATM, CHK1, CHK2 and H2A.X phosphorylation. Wortmannin (a broad inhibitor of PIKKs) and CGK733 (a specific ATM inhibitor), but not LY294002 (a phosphatidylinositol 3-kinase inhibitor) or NU7026 (a DNA-PK specific inhibitor), prevented H2A.X phosphorylation and γH2A.X-positive foci formation in the nuclei, reversed S phase arrest and promoted the HDAB-induced apoptosis, suggesting that HDAB is a DNA damaging agent that can activate the ATM-dependent DNA repair response, thereby contributing to cell cycle arrest. In addition, molecular docking and in vitro activity assays revealed that HDAB can correctly dock into the hydrophobic pocket of PARP-1 and suppress PARP-1 ADP-ribosylation activity. Thus, the results indicated that HDAB can function as an anti-cancer agent by inducing DNA damage and inhibiting PARP activity. PMID:26041102

  20. Tumour inflammasome-derived IL-1β recruits neutrophils and improves local recurrence-free survival in EBV-induced nasopharyngeal carcinoma

    PubMed Central

    Chen, Lih-Chyang; Wang, Li-Jie; Tsang, Nang-Ming; Ojcius, David M; Chen, Chia-Chun; OuYang, Chun-Nan; Hsueh, Chuen; Liang, Ying; Chang, Kai-Ping; Chen, Chiu-Chin; Chang, Yu-Sun

    2012-01-01

    Inflammasomes sense infection and cellular damage and are critical for triggering inflammation through IL-1β production. In carcinogenesis, inflammasomes may have contradictory roles through facilitating antitumour immunity and inducing oncogenic factors. Their function in cancer remains poorly characterized. Here we show that the NLRP3, AIM2 and RIG-I inflammasomes are overexpressed in Epstein-Barr virus (EBV)-associated nasopharyngeal carcinoma (NPC), and expression levels correlate with patient survival. In tumour cells, AIM2 and RIG-I are required for IL-1β induction by EBV genomic DNA and EBV-encoded small RNAs, respectively, while NLRP3 responds to extracellular ATP and reactive oxygen species. Irradiation and chemotherapy can further activate AIM2 and NLRP3, respectively. In mice, tumour-derived IL-1β inhibits tumour growth and enhances survival through host responses. Mechanistically, IL-1β-mediated anti-tumour effects depend on infiltrated immunostimulatory neutrophils. We show further that presence of tumour-associated neutrophils is significantly associated with better survival in NPC patients. Thus, tumour inflammasomes play a key role in tumour control by recruiting neutrophils, and their expression levels are favourable prognostic markers and promising therapeutic targets in patients. PMID:23065753

  1. Discovery of a dual-targeting organometallic ruthenium complex with high activity inducing early stage apoptosis of cancer cells.

    PubMed

    Du, Jun; Zhang, Erlong; Zhao, Yao; Zheng, Wei; Zhang, Yang; Lin, Yu; Wang, Zhaoying; Luo, Qun; Wu, Kui; Wang, Fuyi

    2015-12-01

    Ruthenium based complexes are promising antitumour candidates due to their lower toxicity and better water-solubility compared to the platinum antitumour complexes. An epidermal growth factor receptor (EGFR) has been found to be overexpressed in a large set of tumour cells. In this work, a series of organoruthenium complexes containing EGFR-inhibiting 4-anilinoquinazoline pharmacophores were synthesised and characterised. These complexes exhibited excellent inhibitory activity against EGFR and high affinity to interact with DNA via minor groove binding, featuring dual-targeting properties. In vitro screening demonstrated that the as-prepared ruthenium complexes are anti-proliferating towards a series of cancer cell lines, in particular the non-small-cell lung cancer cell line A549. Fluorescence-activated cell sorting analysis and fluorescence microscopy revealed that the most active complex 3 induced much more early-stage cell apoptosis than its cytotoxic arene ruthenium analogue and the EGFR-inhibiting 4-anilinoquinazolines, verifying the synergetic effect of the two mono-functional pharmacophores. PMID:26446567

  2. Tumour suppressor genes in chemotherapeutic drug response

    PubMed Central

    Lai, Dulcie; Visser-Grieve, Stacy; Yang, Xiaolong

    2012-01-01

    Since cancer is one of the leading causes of death worldwide, there is an urgent need to find better treatments. Currently, the use of chemotherapeutics remains the predominant option for cancer therapy. However, one of the major obstacles for successful cancer therapy using these chemotherapeutics is that patients often do not respond or eventually develop resistance after initial treatment. Therefore identification of genes involved in chemotherapeutic response is critical for predicting tumour response and treating drug-resistant cancer patients. A group of genes commonly lost or inactivated are tumour suppressor genes, which can promote the initiation and progression of cancer through regulation of various biological processes such as cell proliferation, cell death and cell migration/invasion. Recently, mounting evidence suggests that these tumour suppressor genes also play a very important role in the response of cancers to a variety of chemotherapeutic drugs. In the present review, we will provide a comprehensive overview on how major tumour suppressor genes [Rb (retinoblastoma), p53 family, cyclin-dependent kinase inhibitors, BRCA1 (breast-cancer susceptibility gene 1), PTEN (phosphatase and tensin homologue deleted on chromosome 10), Hippo pathway, etc.] are involved in chemotherapeutic drug response and discuss their applications in predicting the clinical outcome of chemotherapy for cancer patients. We also propose that tumour suppressor genes are critical chemotherapeutic targets for the successful treatment of drug-resistant cancer patients in future applications. PMID:22762204

  3. Neutron Activated Samarium-153 Microparticles for Transarterial Radioembolization of Liver Tumour with Post-Procedure Imaging Capabilities

    PubMed Central

    Hashikin, Nurul Ab. Aziz; Yeong, Chai-Hong; Abdullah, Basri Johan Jeet; Ng, Kwan-Hoong; Chung, Lip-Yong; Dahalan, Rehir; Perkins, Alan Christopher

    2015-01-01

    Introduction Samarium-153 (153Sm) styrene divinylbenzene microparticles were developed as a surrogate for Yttrium-90 (90Y) microspheres in liver radioembolization therapy. Unlike the pure beta emitter 90Y, 153Sm possess both therapeutic beta and diagnostic gamma radiations, making it possible for post-procedure imaging following therapy. Methods The microparticles were prepared using commercially available cation exchange resin, Amberlite IR-120 H+ (620–830 μm), which were reduced to 20–40 μm via ball mill grinding and sieve separation. The microparticles were labelled with 152Sm via ion exchange process with 152SmCl3, prior to neutron activation to produce radioactive 153Sm through 152Sm(n,γ)153Sm reaction. Therapeutic activity of 3 GBq was referred based on the recommended activity used in 90Y-microspheres therapy. The samples were irradiated in 1.494 x 1012 n.cm-2.s-1 neutron flux for 6 h to achieve the nominal activity of 3.1 GBq.g-1. Physicochemical characterisation of the microparticles, gamma spectrometry, and in vitro radiolabelling studies were carried out to study the performance and stability of the microparticles. Results Fourier Transform Infrared (FTIR) spectroscopy of the Amberlite IR-120 resins showed unaffected functional groups, following size reduction of the beads. However, as shown by the electron microscope, the microparticles were irregular in shape. The radioactivity achieved after 6 h neutron activation was 3.104 ± 0.029 GBq. The specific activity per microparticle was 53.855 ± 0.503 Bq. Gamma spectrometry and elemental analysis showed no radioactive impurities in the samples. Radiolabelling efficiencies of 153Sm-Amberlite in distilled water and blood plasma over 48 h were excellent and higher than 95%. Conclusion The laboratory work revealed that the 153Sm-Amberlite microparticles demonstrated superior characteristics for potential use in hepatic radioembolization. PMID:26382059

  4. Tumours of the thymus

    PubMed Central

    Sellors, T. Holmes; Thackray, A. C.; Thomson, A. D.

    1967-01-01

    Eighty-eight cases of thymoma are discussed with the object of trying to co-ordinate the histological and clinical features. The pathological specimens were in all cases obtained at operation. The pathology classification introduced by Thomson and Thackray in 1957 has been found to correspond adequately with the clinical pattern. The most common groups of tumours are basically epithelial and can be separated into five or six subdivisions, each of which has a separate pattern of behaviour. Lymphoid and teratomatous tumours also occur, but there were only two examples in this series. Clinically, separation of patients who suffered from myasthenia (38) and those who did not (50) affords the first main grouping. The majority of patients who had myasthenia gravis had tumours classified as epidermoid (19) and lymphoepithelial (14), the former with a more malignant appearance and behaviour than the latter. Removal of the tumour with or without radiation gave considerable and sometimes complete relief from myasthenic symptoms. Non-myasthenic thymoma (50) was usually discovered as a result of pressure signs or in the course of routine radiography. Spindle or oval celled tumours followed a benign pattern whereas undifferentiated thymoma was in every sense malignant, as also were teratomatous growths. Granulomatous or Hodgkin-like thymomas were of special interest and had an unpredictable course, some patients surviving many years after what was regarded as inadequate treatment. The place of radiotherapy as a pre- or post-operative agent complementary to surgery is discussed. Images PMID:6033387

  5. Tumours of the ovary

    PubMed Central

    Nielsen, Svend W.; Misdorp, W.; McEntee, Kenneth

    1976-01-01

    Ovarian tumours are common in animals, the majority occurring in bitches and cows. The two most important germ cell tumours were dysgerminoma and teratoma; these morphologically resemble their counterparts in women, with the exception that teratomas in animals tend less to malignancy. The granulosa cell tumour is the most frequent sex cord-stromal tumour in all six species and it may contain luteinized areas or show differentiation towards a Sertoli cell pattern. The canine papillary adenoma and papillary adenocarcinoma, which are as common as granulosa tumours, have several features in common with their counterparts in women: they are of similar histological appearance, are frequently bilateral, and the adenocarcinomas have a great propensity for peritoneal implantation metastasis. Ovarian cysts are frequent in the bitch, sow, and cow and may originate from five different anatomical structures in the ovary. ImagesFig. 1Fig. 2 and 3Fig. 20-22Fig. 8-10Fig. 15 and 16Fig. 23Fig. 24Fig. 25Fig. 26Fig. 17-19Fig. 4 and 5Fig. 6 and 7Fig. 11Fig. 12Fig. 13 and 14 PMID:1086151

  6. [Recommendations for the diagnosis and treatment of latent and active tuberculosis in patients with inflammatory joint diseases treated with tumour necrosis factor alpha inhibitors].

    PubMed

    Fonseca, João Eurico; Lucas, Helena; Canhão, Helena; Duarte, Raquel; Santos, Maria José; Villar, Miguel; Faustino, Augusto; Raymundo, Elena

    2006-01-01

    The Portuguese Society of Rheumatology (SPR) and the Portuguese Society of Pulmonology (SPP) have developed guidelines for the diagnosis and treatment of latent tuberculosis infection (LTBI) and active tuberculosis (AT) in patients with inflammatory joint diseases (IJD), namely rheumatoid arthritis, psoriatic arthritis and ankylosing spondylitis, treated with tumour necrosis factor alpha (TNF-alpha) antagonists. Due to the high risk of tuberculosis (TB) in patients with IJD, LTBI and AT screening should be performed as soon as possible, ideally at the moment of IJD diagnosis. Even if TB screening was performed at the beginning of the disease, the evaluation should be repeated before starting anti-TNF-alpha therapy. When TB (LTBI orAT) treatment is indicated, it should be performed before the beginning of anti-TNF-alpha therapy. If the IJD activity requires urgent anti-TNF-alpha therapy, these drugs can be started after two months of antituberculosis therapy in AT cases, or after one month in LTBI cases. Chest X-ray is mandatory for all patients. If abnormal, e.g. Gohn complex, the patient should be treated as LTBI; residual lesions require the exclusion of AT and patients with history of untreated or incomplete TB treatment should be treated as LTBI. In cases of suspected active lesions, AT diagnosis should be confirmed and adequate therapy initiated. Tuberculin skin test (TST), with two units of RT23, should be performed in all patients. If induration is less than 5 mm, the test should be repeated after 1 to 2 weeks, on the opposite forearm, and should be considered negative if the result is again inferior to 5 mm. Positive TST implicates LTBI treatment. IfTST is performed in immunosupressed IJD patients, LTBI treatment should be offered to the patient before starting anti-TNFalpha therapy, even in the presence of a negative test. PMID:17094335

  7. Extra gonadal sclerosing stromal tumour in the transverse mesocolon.

    PubMed

    Mensah, Samuel; Kyei, Ishmael; Ohene-Yeboah, Michael; Adjei, Ernest

    2016-03-01

    Sclerosing stromal tumour (SST) is a rare benign sex cord stromal tumour of the ovary. We report a case of sclerosing stromal tumour of the mesentery in a 32-year-old Para one who presented with intra abdominal mass, menstrual irregularity and secondary infertility. Histopathology and immunohistochemistry of the completely excised tumour was consistent with sclerosing stromal tumour, immunoreactive only to vimentin. No ovarian tissue was found in the sectioned tumour. Her menses became regular and she conceived 3 months after complete excision and delivered after 9 months. Hormonal assay was not done because SST was least suspected. From literature this is the first case of SST in the transverse mesocolon reported in the West African subregion, and may probably be one of the rare cases of hormonally active SST. PMID:27605726

  8. Imaging of rare medullary adrenal tumours in adults.

    PubMed

    Maciel, C A; Tang, Y Z; Coniglio, G; Sahdev, A

    2016-05-01

    Although adrenal medullary tumours are rare, they have important clinical implications. They form a heterogeneous group of tumours, ranging from benign, non-secretory, incidental masses to hormonally active tumours presenting acutely, or malignant tumours with disseminated disease and a poor prognosis. Increasingly, benign masses are incidentally detected due to the widespread use of imaging and routine medical check-ups. This review aims to illustrate the multimodality imaging appearances of rare adrenal medullary tumours, excluding the more common phaeochromocytomas, with clues to the diagnosis and to summarise relevant epidemiological and clinical data. Careful correlation of clinical presentation, hormone profile, and various imaging techniques narrow the differential diagnosis. Image-guided percutaneous adrenal biopsy can provide a definitive diagnosis, allowing for conservative management in selected cases. A close collaboration between the radiologist, endocrinologist, and surgeon is of the utmost importance in the management of these tumours. PMID:26944698

  9. Hypoxia-induced nitric oxide production and tumour perfusion is inhibited by pegylated arginine deiminase (ADI-PEG20)

    PubMed Central

    Burrows, Natalie; Cane, Gaelle; Robson, Mathew; Gaude, Edoardo; J. Howat, William; Szlosarek, Peter W.; Pedley, R. Barbara; Frezza, Christian; Ashcroft, Margaret; Maxwell, Patrick H.

    2016-01-01

    The hypoxic tumour microenvironment represents an aggressive, therapy-resistant compartment. As arginine is required for specific hypoxia-induced processes, we hypothesised that arginine-deprivation therapy may be useful in targeting hypoxic cancer cells. We explored the effects of the arginine-degrading agent ADI-PEG20 on hypoxia-inducible factor (HIF) activation, the hypoxia-induced nitric oxide (NO) pathway and proliferation using HCT116 and UMUC3 cells and xenografts. The latter lack argininosuccinate synthetase (ASS1) making them auxotrophic for arginine. In HCT116 cells, ADI-PEG20 inhibited hypoxic-activation of HIF-1α and HIF-2α, leading to decreased inducible-nitric oxide synthase (iNOS), NO-production, and VEGF. Interestingly, combining hypoxia and ADI-PEG20 synergistically inhibited ASS1. ADI-PEG20 inhibited mTORC1 and activated the unfolded protein response providing a mechanism for inhibition of HIF and ASS1. ADI-PEG20 inhibited tumour growth, impaired hypoxia-associated NO-production, and decreased vascular perfusion. Expression of HIF-1α/HIF-2α/iNOS and VEGF were reduced, despite an increased hypoxic tumour fraction. Similar effects were observed in UMUC3 xenografts. In summary, ADI-PEG20 inhibits HIF-activated processes in two tumour models with widely different arginine biology. Thus, ADI-PEG20 may be useful in the clinic to target therapy-resistant hypoxic cells in ASS1-proficient tumours and ASS1-deficient tumours. PMID:26972697

  10. Stress-mediated Sin3B activation leads to negative regulation of subset of p53 target genes

    PubMed Central

    Kadamb, Rama; Mittal, Shilpi; Bansal, Nidhi; Saluja, Daman

    2015-01-01

    The multiprotein SWI-independent 3 (Sin3)–HDAC (histone deacetylase) corepressor complex mediates gene repression through its interaction with DNA-binding factors and recruitment of chromatin-modifying proteins on to the promoters of target gene. Previously, an increased expression of Sin3B and tumour suppressor protein, p53 has been established upon adriamycin treatment. We, now provide evidence that Sin3B expression is significantly up-regulated under variety of stress conditions and this response is not stress-type specific. We observed that Sin3B expression is significantly up-regulated both at transcript and at protein level upon DNA damage induced by bleomycin drug, a radiomimetic agent. This increase in Sin3B expression upon stress is found to be p53-dependent and is associated with enhanced interaction of Sin3B with Ser15 phosphorylated p53. Binding of Sin3–HDAC repressor complex on to the promoters of p53 target genes influences gene regulation by altering histone modifications (H3K9me3 and H3K27me3) at target genes. Furthermore, knockdown of Sin3B by shRNA severely compromises p53-mediated gene repression under stress conditions. Taken together, these results suggest that stress-induced Sin3B activation is p53-dependent and is essential for p53-mediated repression of its selective target genes. The present study has an implication in understanding the transrepression mechanism of p53 under DNA damaging conditions. PMID:26181367

  11. Low density lipoprotein for cytotoxic drug targeting: improved activity of elliptinium derivative against B16 melanoma in mice.

    PubMed Central

    Samadi-Baboli, M.; Favre, G.; Canal, P.; Soula, G.

    1993-01-01

    Significant low density lipoprotein (LDL) uptake by tumour cells led to the use of LDL as a discriminatory vehicle for the delivery of cytotoxic drugs. In the current study, the lipophilic elliptinium derivative, elliptinium-oleate (OL-NME), was incorporated into LDL to reach an incorporation level of 400 molecules per LDL particle. The OL-NME-LDL complex showed cytotoxic effects on normal human fibroblasts while the cytotoxicity was not observed on receptor-defective human fibroblasts, indicating the ability of the complex to be preferentially metabolised by the LDL receptor. In vivo metabolism of the complex was related to the LDL receptor pathway. The metabolic clearance was the same for native LDL (17.1 ml h-1) and OL-NME-LDL complex (16.2 ml h-1). LDL incorporated OL-NME enhanced the anti-tumour activity against murine B16 melanoma model; this resulted from increased efficacy for OL-NME-LDL at doses equal to free 9-OH-NME (157 vs 76 of Increase Life Span (ILS) (%) values after intraperitoneal (i.p.) drug injection on i.p. implanted tumour model and 45 vs -2 ILS (%) values after intravenous drug injection on subcutaneous implanted tumour model). These data suggest that LDL improves the potency of lipophilic cytotoxic drugs against tumours that express LDL receptor activity. PMID:8347487

  12. Xenobiotic-metabolizing enzymes in canine mammary tumours.

    PubMed

    Kumaraguruparan, R; Subapriya, R; Balachandran, C; Manohar, B Murali; Thangadurai, A; Nagini, S

    2006-09-01

    Mammary tumours are the most common neoplasms in female dogs. The present study was designed to evaluate the relationship between different clinical stages with activities of phase I and phase II carcinogen-metabolizing enzymes in canine mammary tumours. The levels of cytochrome P450 and cytochrome b5 and the activities of glutathione S-transferase (GST), gamma-glutamyl transpeptidase (GGT), DT-diaphorase (DTD) and NADPH diaphorase in tumour tissues of 25 bitches was estimated. Enhanced levels of cytochrome P450 and b5 and phase II enzyme activities were observed in tumour tissues compared to the corresponding uninvolved adjacent tissues. The magnitude of the changes in phase I and phase II enzyme status was, however, more pronounced in stages I and II compared to stages III and IV. The results suggest that the balance between phase I carcinogen activation and phase II detoxification systems may play an important role in canine mammary tumour development. PMID:16014333

  13. Radiotherapy for ocular tumours.

    PubMed

    Stannard, C; Sauerwein, W; Maree, G; Lecuona, K

    2013-02-01

    Ocular tumours present a therapeutic challenge because of the sensitive tissues involved and the necessity to destroy the tumour while minimising visual loss. Radiotherapy (RT) is one of several modalites used apart from surgery, laser, cryotherapy, and chemotherapy. Both external beam RT (EBRT) and brachytherapy are used. Tumours of the bulbar conjunctiva, squamous carcinoma and malignant melanoma, can be treated with a radioactive plaque: strontium-90, ruthenium-106 (Ru-106), or iodine-125 (I-125), after excision. If the tumour involves the fornix or tarsal conjunctiva, proton therapy can treat the conjunctiva and spare most of the eye. Alternatively, an I-125 interstitial implant can be used with shielding of the cornea and lens. Conjunctival mucosal-associated lymphoid tissue lymphoma can be treated with an anterior electron field with lens shielding and 25-30 Gray (Gy) in 2 Gy fractions. Discrete retinoblastoma (RB), too large for cryotherapy or thermolaser, or recurrent after these modalities, can be treated with plaque therapy, I-125, or Ru-106. For large RB, multiple tumours, or vitreous seeds the whole eye can be treated with an I-125 applicator, sparing the bony orbit, or with EBRT, under anaesthetic, using X-rays or proton therapy with vacuum contact lenses to fix the eyes in the required position. Post-enucleated orbits at risk for recurrent RB can be treated with an I-125 implant with shielding to reduce the dose to the bony orbit. Uveal malignant melanomas can be treated with plaque or proton therapy with excellent local control. Preservation of vision will depend on the initial size and location of the tumour. PMID:23174750

  14. Radiotherapy for ocular tumours

    PubMed Central

    Stannard, C; Sauerwein, W; Maree, G; Lecuona, K

    2013-01-01

    Ocular tumours present a therapeutic challenge because of the sensitive tissues involved and the necessity to destroy the tumour while minimising visual loss. Radiotherapy (RT) is one of several modalites used apart from surgery, laser, cryotherapy, and chemotherapy. Both external beam RT (EBRT) and brachytherapy are used. Tumours of the bulbar conjunctiva, squamous carcinoma and malignant melanoma, can be treated with a radioactive plaque: strontium-90, ruthenium-106 (Ru-106), or iodine-125 (I-125), after excision. If the tumour involves the fornix or tarsal conjunctiva, proton therapy can treat the conjunctiva and spare most of the eye. Alternatively, an I-125 interstitial implant can be used with shielding of the cornea and lens. Conjunctival mucosal-associated lymphoid tissue lymphoma can be treated with an anterior electron field with lens shielding and 25–30 Gray (Gy) in 2 Gy fractions. Discrete retinoblastoma (RB), too large for cryotherapy or thermolaser, or recurrent after these modalities, can be treated with plaque therapy, I-125, or Ru-106. For large RB, multiple tumours, or vitreous seeds the whole eye can be treated with an I-125 applicator, sparing the bony orbit, or with EBRT, under anaesthetic, using X-rays or proton therapy with vacuum contact lenses to fix the eyes in the required position. Post-enucleated orbits at risk for recurrent RB can be treated with an I-125 implant with shielding to reduce the dose to the bony orbit. Uveal malignant melanomas can be treated with plaque or proton therapy with excellent local control. Preservation of vision will depend on the initial size and location of the tumour. PMID:23174750

  15. Interaction with extracellular matrix proteins influences Lsh/Ity/Bcg (candidate Nramp) gene regulation of macrophage priming/activation for tumour necrosis factor-alpha and nitrite release.

    PubMed

    Formica, S; Roach, T I; Blackwell, J M

    1994-05-01

    The murine resistance gene Lsh/Ity/Bcg regulates activation of macrophages for tumour necrosis factor-alpha (TNF-alpha)-dependent production of nitric oxide mediating antimicrobial activity against Leishmania, Salmonella and Mycobacterium. As Lsh is differentially expressed in macrophages from different tissue sites, experiments were performed to determine whether interaction with extracellular matrix (ECM) proteins would influence the macrophage TNF-alpha response. Plating of bone marrow-derived macrophages onto purified fibrinogen or fibronectin-rich L929 cell-derived matrices, but not onto mannan, was itself sufficient to stimulate TNF-alpha release, with significantly higher levels released from congenic B10.L-Lshr compared to C57BL/10ScSn (Lshs) macrophages. Only macrophages plated onto fibrinogen also released measurable levels of nitrites, again higher in Lshr compared to Lshs macrophages. Addition of interferon-gamma (IFN-gamma), but not bacterial lipopolysaccharide or mycobacterial lipoarabinomannan, as a second signal enhanced the TNF-alpha and nitrite responses of macrophages plated onto fibrinogen, particularly in the Lshr macrophages. Interaction with fibrinogen and fibronectin also primed macrophages for an enhanced TNF-alpha response to leishmanial parasites, but this was only translated into enhanced nitrite responses in the presence of IFN-gamma. In these experiments, Lshr macrophages remained superior in their TNF-alpha responses throughout, but to a degree which reflected the magnitude of the difference observed on ECM alone. Hence, the specificity for the enhanced TNF-alpha responses of Lshr macrophages lay in their interaction with fibrinogen and fibronectin ECM, while a differential nitrite response was only observed with fibrinogen and/or IFN-gamma. The results are discussed in relation to the possible function of the recently cloned candidate gene Nramp, which has structural identity to eukaryote transporters and an N-terminal cytoplasmic

  16. Overcoming the immortality of tumour cells by telomere and telomerase based cancer therapeutics--current status and future prospects.

    PubMed

    Kelland, Lloyd R

    2005-05-01

    A key property of malignant tumours is their immortality or limitless replicative potential. Cell replication is associated with the maintenance of telomeres and in the great majority of cases, through the reactivation of the reverse transcriptase telomerase. Targeting the telomere/telomerase machinery offers a novel and potentially broad-spectrum anticancer therapeutic strategy since telomerase is constitutively overexpressed in the vast majority of human cancers. Telomeres are also critically short in most tumours compared to normal tissues. Strategies that exploit these differences include the direct targeting of components of telomerase: the protein component hTERT or RNA component hTR. Examples of such agents include the small molecule hTERT inhibitor BIBR1532 and GRN163L, a thio-phosphoramidate oligonucleotide targeting the template region of hTR as a "template antagonist". Anti-tumour effects have been observed in both cell lines and, especially for GRN163L, in xenografted human tumours in mice. Effects, however, are largely dependent upon initial telomere length, which can result in a substantial lag before antitumour activity is observed in tumours possessing relatively long telomeres. An alternative approach is to target the telomere itself (Telomere Targeting Agents, TTAs). Several classes of small molecules have been described that induce the G-rich single-stranded overhang of telomeric DNA to fold into 4-stranded G-quadruplex structures. Such folding is incompatible with telomerase function and may induce rapid telomere uncapping. These molecules have shown potent telomerase inhibition in nanomolar concentrations in vitro and the rapid induction of senescence in cancer cells. The trisubstituted acridine based TTA, BRACO19, has demonstrated single agent activity against human tumour xenografts with anti-tumour effects apparent from only 7 days of treatment. In the near future, it is expected that lead examples from both the direct telomerase targeted

  17. Tumour Cell Lines HT-29 and FaDu Produce Proinflammatory Cytokines and Activate Neutrophils In Vitro: Possible Applications for Neutrophil-Based Antitumour Treatment

    PubMed Central

    Brú, Antonio; Souto, Juan-Carlos; Alcolea, Sonia; Antón, Rosa; Remacha, Angel; Camacho, Mercedes; Soler, Marta; Brú, Isabel; Porres, Amelia; Vila, Luis

    2009-01-01

    There is evidence that polymorphonuclear neutrophils (PMNs) can exert severe antineoplastic effects. Cross-talk between tumour cells and endothelial cells (ECs) is necessary for the accumulation of PMN around a tumour. This work reports the ability of two PMN-sensitive, human, permanent cell lines—colorectal adenocarcinoma (HT-29) and pharyngeal squamous-cell carcinoma (FaDu) cells—to act as inflammatory foci. PMNs were cytotoxic to both lines, the adhesion of the PMNs to the tumour cells being important in this effect. The tumour cells released appreciable amounts of IL-8 and GROα, and induced the transmigration of PMN through human microvascular-EC monolayers. Conditioning media associated with both lines induced the adhesion of PMN and the surface expression of ICAM-1 in microvascular-EC. In addition, FaDu-conditioning-medium strongly induced the production of proinflammatory cytokines by microvascular-EC. These results support the idea that tumour cells might normally induce a potent acute inflammatory response, leading to their own destruction. PMID:20169105

  18. Parallel evolution of tumour subclones mimics diversity between tumours.

    PubMed

    Martinez, Pierre; Birkbak, Nicolai Juul; Gerlinger, Marco; McGranahan, Nicholas; Burrell, Rebecca A; Rowan, Andrew J; Joshi, Tejal; Fisher, Rosalie; Larkin, James; Szallasi, Zoltan; Swanton, Charles

    2013-08-01

    Intratumour heterogeneity (ITH) may foster tumour adaptation and compromise the efficacy of personalized medicine approaches. The scale of heterogeneity within a tumour (intratumour heterogeneity) relative to genetic differences between tumours (intertumour heterogeneity) is unknown. To address this, we obtained 48 biopsies from eight stage III and IV clear cell renal cell carcinomas (ccRCCs) and used DNA copy-number analyses to compare biopsies from the same tumour with 440 single tumour biopsies from the Cancer Genome Atlas (TCGA). Unsupervised hierarchical clustering of TCGA and multi-region ccRCC samples revealed segregation of samples from the same tumour into unrelated clusters; 25% of multi-region samples appeared more similar to unrelated samples than to any other sample originating from the same tumour. We found that the majority of recurrent DNA copy number driver aberrations in single biopsies were not present ubiquitously in late-stage ccRCCs and were likely to represent subclonal events acquired during tumour progression. Such heterogeneous subclonal genetic alterations within individual tumours may impair the identification of robust ccRCC molecular subtypes classified by distinct copy number alterations and clinical outcomes. The co-existence of distinct subclonal copy number events in different regions of individual tumours reflects the diversification of individual ccRCCs through multiple evolutionary routes and may contribute to tumour sampling bias and impact upon tumour progression and clinical outcome. PMID:23716380

  19. Proatherogenic macrophage activities are targeted by the flavonoid quercetin.

    PubMed

    Lara-Guzman, Oscar J; Tabares-Guevara, Jorge H; Leon-Varela, Yudy M; Álvarez, Rafael M; Roldan, Miguel; Sierra, Jelver A; Londoño-Londoño, Julian A; Ramirez-Pineda, Jose R

    2012-11-01

    Many studies have demonstrated that the flavonoid quercetin protects against cardiovascular disease (CVD) and related risk factors. Atherosclerosis, the underlying cause of CVD, is also attenuated by oral quercetin administration in animal models. Although macrophages are key players during fatty streak formation and plaque progression and aggravation, little is known about the effects of quercetin on atherogenic macrophages. Here, we report that primary bone marrow-derived macrophages internalized less oxidized low-density lipoprotein (oxLDL) and accumulated less intracellular cholesterol in the presence of quercetin. This reduction of foam cell formation correlated with reduced surface expression of the oxLDL receptor CD36. Quercetin also targeted the lipopolysaccharide-dependent, oxLDL-independent pathway of lipid droplet formation in macrophages. In oxLDL-stimulated macrophages, quercetin inhibited reactive oxygen species production and interleukin (IL)-6 secretion. In a system that evaluated cholesterol crystal-induced IL-1β secretion via nucleotide-binding domain and leucine-rich repeat containing protein 3 inflammasome activation, quercetin also exhibited an inhibitory effect. Dyslipidemic apolipoprotein E-deficient mice chronically treated with intraperitoneal quercetin injections had smaller atheromatous lesions, reduced lipid deposition, and less macrophage and T cell inflammatory infiltrate in the aortic roots than vehicle-treated animals. Serum levels of total cholesterol and the lipid peroxidation product malondialdehyde were also reduced in these mice. Our results demonstrate that quercetin interferes with both key proatherogenic activities of macrophages, namely foam cell formation and pro-oxidant/proinflammatory responses, and these effects may explain the atheroprotective properties of this common flavonoid. PMID:22869926

  20. Target of rapamycin activation predicts lifespan in fruit flies

    PubMed Central

    Scialò, Filippo; Sriram, Ashwin; Naudí, Alba; Ayala, Victoria; Jové, Mariona; Pamplona, Reinald; Sanz, Alberto

    2015-01-01

    Aging and age-related diseases are one of the most important health issues that the world will confront during the 21st century. Only by understanding the proximal causes will we be able to find treatments to reduce or delay the onset of degenerative diseases associated with aging. Currently, the prevalent paradigm in the field is the accumulation of damage. However, a new theory that proposes an alternative explanation is gaining momentum. The hyperfunction theory proposes that aging is not a consequence of a wear and tear process, but a result of the continuation of developmental programs during adulthood. Here we use Drosophila melanogaster, where evidence supporting both paradigms has been reported, to identify which parameters that have been previously related with lifespan best predict the rate of aging in wild type flies cultured at different temperatures. We find that mitochondrial function and mitochondrial reactive oxygen species (mtROS) generation correlates with metabolic rate, but not with the rate of aging. Importantly, we find that activation of nutrient sensing pathways (i.e. insulin-PI3K/Target of rapamycin (Tor) pathway) correlates with lifespan, but not with metabolic rate. Our results, dissociate metabolic rate and lifespan in wild type flies and instead link nutrient sensing signaling with longevity as predicted by the hyperfunction theory. PMID:26259964

  1. Synthesis and in vitro activity of platinum(II) complexes of two fluorenylspirohydantoins against a human tumour cell line

    PubMed Central

    Marinova, Petja; Marinov, Marin; Kazakova, Maria; Feodorova, Yana; Penchev, Plamen; Sarafian, Victoria; Stoyanov, Neyko

    2014-01-01

    This paper presents a method for synthesis and cytotoxicity of new platinum(II) complexes of (9′-fluorene)-spiro-5-hydantoin (L1) and (9′-fluorene)-spiro-5-(2-thiohydantoin) (L2). The new obtained complexes were studied by elemental analysis: ultraviolet–visible, attenuated total reflection Fourier transform infrared (ATR-FTIR), and 1H- and 13C-NMR for Pt(II) compounds and additionally Raman spectroscopy for free ligands. Based on the experimental data, the most probable structure of the complexes is suggested. In the present study, we have examined cytotoxic activity of (9′-fluorene)-spiro-5-hydantoin (L1) and (9′-fluorene)-spiro-5-(2-thiohydantoin) (L2) and their Pt(II) complexes on the retinoblastoma cell line WERI-Rb-1. PMID:26019515

  2. Presence of a tumour-inhibiting factor (TIF) in sera from normal but not tumour-bearing mice.

    PubMed Central

    Kim, B S; Chin, D K

    1980-01-01

    Some plasmacytomas produce myeloma proteins with known antibody specificities and the secretion of these proteins by individual tumour cells can be determined using haemolytic plaque assay. After a 3 day culture of mouse plasmacytoma cells in medium containing 10% normal mouse serum, the number of plaques was reduced to less than 10% when compared to that of tumour cells incubated with either foetal calf serum or normal rabbit serum. However, tumour cells incubated with sera from mice bearing TEPC-15, McPC-603, or MOPC-315 plasmacytomas displayed control levels of plaques. The production of plaques paralleled the viability of tumour cells suggesting that the reduction of plaque formation is due to the decreased viable cell number. The tumour-inhibiting activity was recovered from the fraction of apparent molecular weight of 300,000-400,000 after a partial purification using an agarose (A 0.5 M) column. This fraction, however, did not suppress in vitro induction of antibody production. Kinetic experiments using sera obtained sequentially from individual mice receiving either TEPC-15 or MOPC-315 plasmacytomas further indicated that the tumour-inhibiting activity is severely reduced during a 2 week period after tumour inoculation. The inhibition of tumour cells did not appear to be specific since tumour cells of three plasmacytomas (TEPC-15, MOPC-167 and MOPC-315), a mastocytoma (P815) and a lymphoma (EL-4) displayed a similar susceptibility to normal serum. PMID:7002770

  3. Tumour suppressor protein p53 regulates the stress activated bilirubin oxidase cytochrome P450 2A6.

    PubMed

    Hu, Hao; Yu, Ting; Arpiainen, Satu; Lang, Matti A; Hakkola, Jukka; Abu-Bakar, A'edah

    2015-11-15

    Human cytochrome P450 (CYP) 2A6 enzyme has been proposed to play a role in cellular defence against chemical-induced oxidative stress. The encoding gene is regulated by various stress activated transcription factors. This paper demonstrates that p53 is a novel transcriptional regulator of the gene. Sequence analysis of the CYP2A6 promoter revealed six putative p53 binding sites in a 3kb proximate promoter region. The site closest to transcription start site (TSS) is highly homologous with the p53 consensus sequence. Transfection with various stepwise deletions of CYP2A6-5'-Luc constructs--down to -160bp from the TSS--showed p53 responsiveness in p53 overexpressed C3A cells. However, a further deletion from -160 to -74bp, including the putative p53 binding site, totally abolished the p53 responsiveness. Electrophoretic mobility shift assay with a probe containing the putative binding site showed specific binding of p53. A point mutation at the binding site abolished both the binding and responsiveness of the recombinant gene to p53. Up-regulation of the endogenous p53 with benzo[α]pyrene--a well-known p53 activator--increased the expression of the p53 responsive positive control and the CYP2A6-5'-Luc construct containing the intact p53 binding site but not the mutated CYP2A6-5'-Luc construct. Finally, inducibility of the native CYP2A6 gene by benzo[α]pyrene was demonstrated by dose-dependent increases in CYP2A6 mRNA and protein levels along with increased p53 levels in the nucleus. Collectively, the results indicate that p53 protein is a regulator of the CYP2A6 gene in C3A cells and further support the putative cytoprotective role of CYP2A6. PMID:26343999

  4. Targeting leukemia stem cells: which pathways drive self-renewal activity in T-cell acute lymphoblastic leukemia?

    PubMed Central

    Belmonte, M.; Hoofd, C.; Weng, A.P.; Giambra, V.

    2016-01-01

    T-Cell acute lymphoblastic leukemia (t-all) is a malignancy of white blood cells, characterized by an uncontrolled accumulation of T-cell progenitors. During leukemic progression, immature T cells grow abnormally and crowd into the bone marrow, preventing it from making normal blood cells and spilling out into the bloodstream. Recent studies suggest that only discrete cell populations that possess the ability to recreate the entire tumour might be responsible for the initiation and propagation of t-all. Those unique cells are commonly called “cancer stem cells” or, in the case of hematopoietic malignancies, “leukemia stem cells” (lscs). Like normal hematopoietic stem cells, lscs are thought to be capable of self-renewal, during which, by asymmetrical division, they give rise to an identical copy of themselves as well as to a daughter cell that is no longer capable of self-renewal activity and represents a more “differentiated” progeny. Here, we review the main pathways of self-renewal activity in lscs, focusing on their involvement in the maintenance and development of t-all. New stem cell–directed therapies and lsc-targeted agents are also discussed. PMID:26966402

  5. 13 CFR 124.509 - What are non-8(a) business activity targets?

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... activity targets and are expressed as a percentage of total revenue. The targets call for an increase in... obtain non-8(a) revenues. (e) Waiver of sole source prohibition. (1) The AA/BD, or his or her designee... activity targets? 124.509 Section 124.509 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION...

  6. EphrinB2 repression through ZEB2 mediates tumour invasion and anti-angiogenic resistance

    PubMed Central

    Depner, C.; zum Buttel, H.; Böğürcü, N.; Cuesta, A. M.; Aburto, M. R.; Seidel, S.; Finkelmeier, F.; Foss, F.; Hofmann, J.; Kaulich, K.; Barbus, S.; Segarra, M.; Reifenberger, G.; Garvalov, B. K.; Acker, T.; Acker-Palmer, A.

    2016-01-01

    Diffuse invasion of the surrounding brain parenchyma is a major obstacle in the treatment of gliomas with various therapeutics, including anti-angiogenic agents. Here we identify the epi-/genetic and microenvironmental downregulation of ephrinB2 as a crucial step that promotes tumour invasion by abrogation of repulsive signals. We demonstrate that ephrinB2 is downregulated in human gliomas as a consequence of promoter hypermethylation and gene deletion. Consistently, genetic deletion of ephrinB2 in a murine high-grade glioma model increases invasion. Importantly, ephrinB2 gene silencing is complemented by a hypoxia-induced transcriptional repression. Mechanistically, hypoxia-inducible factor (HIF)-1α induces the EMT repressor ZEB2, which directly downregulates ephrinB2 through promoter binding to enhance tumour invasiveness. This mechanism is activated following anti-angiogenic treatment of gliomas and is efficiently blocked by disrupting ZEB2 activity. Taken together, our results identify ZEB2 as an attractive therapeutic target to inhibit tumour invasion and counteract tumour resistance mechanisms induced by anti-angiogenic treatment strategies. PMID:27470974

  7. Targeting the AKT pathway: Repositioning HIV protease inhibitors as radiosensitizers

    PubMed Central

    Goda, Jayant S.; Pachpor, Tejaswini; Basu, Trinanjan; Chopra, Supriya; Gota, Vikram

    2016-01-01

    Cellular resistance in tumour cells to different therapeutic approaches has been a limiting factor in the curative treatment of cancer. Resistance to therapeutic radiation is a common phenomenon which significantly reduces treatment options and impacts survival. One of the mechanisms of acquiring resistance to ionizing radiation is the overexpression or activation of various oncogenes like the EGFR (epidermal growth factor receptor), RAS (rat sarcoma) oncogene or loss of PTEN (phosphatase and tensin homologue) which in turn activates the phosphatidyl inositol 3-kinase/protein kinase B (PI3-K)/AKT pathway responsible for radiation resistance in various tumours. Blocking the pathway enhances the radiation response both in vitro and in vivo. Due to the differential activation of this pathway (constitutively activated in tumour cells and not in the normal host cells), it is an excellent candidate target for molecular targeted therapy to enhance radiation sensitivity. In this regard, HIV protease inhibitors (HPIs) known to interfere with PI3-K/AKT signaling in tumour cells, have been shown to sensitize various tumour cells to radiation both in vitro and in vivo. As a result, HPIs are now being investigated as possible radiosensitizers along with various chemotherapeutic drugs. This review describes the mechanisms by which PI3-K/AKT pathway causes radioresistance and the role of HIV protease inhibitors especially nelfinavir as a potential candidate drug to target the AKT pathway for overcoming radioresistance and its use in various clinical trials for different malignancies. PMID:27121513

  8. Frameless stereotactic radiosurgery for the treatment of primary intracranial tumours in dogs.

    PubMed

    Mariani, C L; Schubert, T A; House, R A; Wong, M A; Hopkins, A L; Barnes Heller, H L; Milner, R J; Lester, N V; Lurie, D M; Rajon, D A; Friedman, W A; Bova, F J

    2015-12-01

    Stereotactic radiosurgery (SRS) is a procedure that delivers a single large radiation dose to a well-defined target. Here, we describe a frameless SRS technique suitable for intracranial targets in canines. Medical records of dogs diagnosed with a primary intracranial tumour by imaging or histopathology that underwent SRS were retrospectively reviewed. Frameless SRS was used successfully to treat tumours in 51 dogs with a variety of head sizes and shapes. Tumours diagnosed included 38 meningiomas, 4 pituitary tumours, 4 trigeminal nerve tumours, 3 gliomas, 1 histiocytic sarcoma and 1 choroid plexus tumour. Median survival time was 399 days for all tumours and for dogs with meningiomas; cause-specific survival was 493 days for both cohorts. Acute grade III central nervous system toxicity (altered mentation) occurred in two dogs. Frameless SRS resulted in survival times comparable to conventional radiation therapy, but with fewer acute adverse effects and only a single anaesthetic episode required for therapy. PMID:24007303

  9. Tumour Cell Heterogeneity

    PubMed Central

    Gay, Laura; Baker, Ann-Marie; Graham, Trevor A.

    2016-01-01

    The population of cells that make up a cancer are manifestly heterogeneous at the genetic, epigenetic, and phenotypic levels. In this mini-review, we summarise the extent of intra-tumour heterogeneity (ITH) across human malignancies, review the mechanisms that are responsible for generating and maintaining ITH, and discuss the ramifications and opportunities that ITH presents for cancer prognostication and treatment. PMID:26973786

  10. Pre-target oscillatory brain activity and the attentional blink.

    PubMed

    Petro, Nathan M; Keil, Andreas

    2015-12-01

    Reporting the second of two targets within a stream of distracting words during rapid serial visual presentation (RSVP) is impaired when the targets are separated by a single distractor word, a deficit in temporal attention that has been referred to as the attentional blink (AB). Recent conceptual and empirical work has pointed to pre-target brain states as potential mediators of the AB effect. The current study examined differences in pre-target electrophysiology between correctly and incorrectly reported trials, considering amplitude and phase measures of alpha oscillations as well as the steady-state visual evoked potential (ssVEP) evoked by the RSVP stream. For incorrectly reported trials, relatively lower alpha-band power and greater ssVEP inter-trial phase locking were observed during extended time periods preceding presentation of the first target. These results suggest that facilitated processing of the pre-target distracter stream indexed by reduced alpha and heightened phase locking characterizes a dynamic brain state that predicts lower accuracy in terms of reporting the second target under strict temporal constraints. Findings align with hypotheses in which the AB effect is attributed to neurocognitive factors such as fluctuations in pre-target attention or to cognitive strategies applied at the trial level. PMID:26341931

  11. 78 FR 35612 - Agency Information Collection Activities; Comment Request; Targeted Teacher Shortage Areas...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-13

    ... collection of information from Chief State School Officers to support and document the request for teacher... Agency Information Collection Activities; Comment Request; Targeted Teacher Shortage Areas Nationwide... to this notice will be considered public records. Title of Collection: Targeted Teacher...

  12. Systemic therapy for selected skull base sarcomas: Chondrosarcoma, chordoma, giant cell tumour and solitary fibrous tumour/hemangiopericytoma.

    PubMed

    Colia, Vittoria; Provenzano, Salvatore; Hindi, Nadia; Casali, Paolo G; Stacchiotti, Silvia

    2016-01-01

    This review highlights the data currently available on the activity of systemic therapy in chondrosarcoma, chordoma, giant cell tumour of the bone (GCTB) and solitary fibrous tumour, i.e., four rare sarcomas amongst mesenchymal malignancy arising from the skull base. PMID:27330421

  13. HLA-dependent tumour development: a role for tumour associate macrophages?

    PubMed

    Marchesi, Maddalena; Andersson, Emilia; Villabona, Lisa; Seliger, Barbara; Lundqvist, Andreas; Kiessling, Rolf; Masucci, Giuseppe V

    2013-01-01

    HLA abnormalities on tumour cells for immune escape have been widely described. In addition, cellular components of the tumour microenvironment, in particular myeloid derived suppressor cells (MDSC) and alternatively activated M2 tumour-associated macrophages (TAMs), are involved in tumour promotion, progression, angiogenesis and suppression of anti-tumour immunity. However, the role of HLA in these activities is poorly understood. This review details MHC class I characteristics and describes MHC class I receptors functions. This analysis established the basis for a reflection about the crosstalk among the tumour cells, the TAMs and the cells mediating an immune response.The tumour cells and TAMs exploit MHC class I molecules to modulate the surrounding immune cells. HLA A, B, C and G molecules down-regulate the macrophage myeloid activation through the interaction with the inhibitory LILRB receptors. HLA A, B, C are able to engage inhibitory KIR receptors negatively regulating the Natural Killer and cytotoxic T lymphocytes function while HLA-G induces the secretion of pro-angiogenic cytokines and chemokine thanks to an activator KIR receptor expressed by a minority of peripheral NK cells. The open conformer of classical MHC-I is able to interact with LILRA receptors described as being associated to the Th2-type cytokine response, triggering a condition for the M2 like TAM polarization. In addition, HLA-E antigens on the surface of the TAMs bind the inhibitory receptor CD94/NKG2A expressed by a subset of NK cells and activated cytotoxic T lymphocytes protecting from the cytolysis.Furthermore MHC class II expression by antigen presenting cells is finely regulated by factors provided with immunological capacities. Tumour-associated macrophages show an epigenetically controlled down-regulation of the MHC class II expression induced by the decoy receptor DcR3, a member of the TNFR, which further enhances the M2-like polarization. BAT3, a positive regulator of MHC class

  14. Tirapazamine: a bioreductive anticancer drug that exploits tumour hypoxia.

    PubMed

    Denny, W A; Wilson, W R

    2000-12-01

    Tirapazamine is the second clinical anticancer drug (after porfiromycin) that functions primarily as a hypoxia-selective cytotoxin. Hypoxic cells in tumours are relatively resistant to radiotherapy and to some forms of chemotherapy and are also biologically aggressive, thus representing an important target population in oncology. Tirapazamine undergoes metabolism by reductases to form a transient oxidising radical that can be efficiently scavenged by molecular oxygen in normal tissues to re-form the parent compound. In the absence of oxygen, the oxidising radical abstracts a proton from DNA to form DNA radicals, largely at C4' on the ribose ring. Tirapazamine can also oxidise such DNA radicals to cytotoxic DNA strand breaks. It therefore shows substantial selective cytotoxicity for anoxic cells in culture (typically approximately 100-fold more potent than under oxic conditions) and for the hypoxic subfraction of cells in tumours. Preclinical studies showed enhanced activity of combinations of tirapazamine with radiation (to kill oxygenated cells) and with conventional cytotoxics, especially cisplatin (probably through inhibition of repair of cisplatin DNA cross-links in hypoxic cells). Phase II and III clinical studies of tirapazamine and cisplatin in malignant melanoma and non-small cell lung cancer suggest that the combination is more active than cisplatin alone and preliminary results with advanced squamous cell carcinomas of the head and neck indicate that tirapazamine may enhance the activity of cisplatin with fractionated radiotherapy. PMID:11093359

  15. Bypassing Protein Corona Issue on Active Targeting: Zwitterionic Coatings Dictate Specific Interactions of Targeting Moieties and Cell Receptors.

    PubMed

    Safavi-Sohi, Reihaneh; Maghari, Shokoofeh; Raoufi, Mohammad; Jalali, Seyed Amir; Hajipour, Mohammad J; Ghassempour, Alireza; Mahmoudi, Morteza

    2016-09-01

    Surface functionalization strategies for targeting nanoparticles (NP) to specific organs, cells, or organelles, is the foundation for new applications of nanomedicine to drug delivery and biomedical imaging. Interaction of NPs with biological media leads to the formation of a biomolecular layer at the surface of NPs so-called as "protein corona". This corona layer can shield active molecules at the surface of NPs and cause mistargeting or unintended scavenging by the liver, kidney, or spleen. To overcome this corona issue, we have designed biotin-cysteine conjugated silica NPs (biotin was employed as a targeting molecule and cysteine was used as a zwitterionic ligand) to inhibit corona-induced mistargeting and thus significantly enhance the active targeting capability of NPs in complex biological media. To probe the targeting yield of our engineered NPs, we employed both modified silicon wafer substrates with streptavidin (i.e., biotin receptor) to simulate a target and a cell-based model platform using tumor cell lines that overexpress biotin receptors. In both cases, after incubation with human plasma (thus forming a protein corona), cellular uptake/substrate attachment of the targeted NPs with zwitterionic coatings were significantly higher than the same NPs without zwitterionic coating. Our results demonstrated that NPs with a zwitterionic surface can considerably facilitate targeting yield of NPs and provide a promising new type of nanocarriers in biological applications. PMID:27526263

  16. Multimodality PET/MRI agents targeted to activated macrophages.

    PubMed

    Tu, Chuqiao; Ng, Thomas S C; Jacobs, Russell E; Louie, Angelique Y

    2014-02-01

    The recent emergence of multimodality imaging, particularly the combination of PET and MRI, has led to excitement over the prospect of improving detection of disease. Iron oxide nanoparticles have become a popular platform for the fabrication of PET/MRI probes owing to their advantages of high MRI detection sensitivity, biocompatibility, and biodegradability. In this article, we report the synthesis of dextran-coated iron oxide nanoparticles (DIO) labeled with the positron emitter (64)Cu to generate a PET/MRI probe, and modified with maleic anhydride to increase the negative surface charge. The modified nanoparticulate PET/MRI probe (MDIO-(64)Cu-DOTA) bears repetitive anionic charges on the surface that facilitate recognition by scavenger receptor type A (SR-A), a ligand receptor found on activated macrophages but not on normal vessel walls. MDIO-(64)Cu-DOTA has an average iron oxide core size of 7-8 nm, an average hydrodynamic diameter of 62.7 nm, an r1 relaxivity of 16.8 mM(-1) s(-1), and an r 2 relaxivity of 83.9 mM(-1) s(-1) (37 °C, 1.4 T). Cell studies confirmed that the probe was nontoxic and was specifically taken up by macrophages via SR-A. In comparison with the nonmodified analog, the accumulation of MDIO in macrophages was substantially improved. These characteristics demonstrate the promise of MDIO-(64)Cu-DOTA for identification of vulnerable atherosclerotic plaques via the targeting of macrophages. PMID:24166283

  17. Magnetoresponsive squalenoyl gemcitabine composite nanoparticles for cancer active targeting.

    PubMed

    Arias, José L; Reddy, L Harivardhan; Couvreur, Patrick

    2008-07-15

    heterogeneous structure of these nanoparticles could confer them both magnetic field responsiveness and potential applicability as a drug carrier for active targeting to solid tumors. PMID:18540685

  18. The epigenetics of tumour initiation: cancer stem cells and their chromatin.

    PubMed

    Avgustinova, Alexandra; Benitah, Salvador Aznar

    2016-02-01

    Cancer stem cells (CSCs) have been identified in various tumours and are defined by their potential to initiate tumours upon transplantation, self-renew and reconstitute tumour heterogeneity. Modifications of the epigenome can favour tumour initiation by affecting genome integrity, DNA repair and tumour cell plasticity. Importantly, an in-depth understanding of the epigenomic alterations underlying neoplastic transformation may open new avenues for chromatin-targeted cancer treatment, as these epigenetic changes could be inherently more amenable to inhibition and reversal than hard-wired genomic alterations. Here we discuss how CSC function is affected by chromatin state and epigenomic instability. PMID:26874045

  19. Utilizing the folate receptor for active targeting of cancer nanotherapeutics

    PubMed Central

    Zwicke, Grant L.; Mansoori, G. Ali; Jeffery, Constance J.

    2012-01-01

    The development of specialized nanoparticles for use in the detection and treatment of cancer is increasing. Methods are being proposed and tested that could target treatments more directly to cancer cells, which could lead to higher efficacy and reduced toxicity, possibly even eliminating the adverse effects of damage to the immune system and the loss of quick replicating cells. In this mini-review we focus on recent studies that employ folate nanoconjugates to target the folate receptor. Folate receptors are highly overexpressed on the surface of many tumor types. This expression can be exploited to target imaging molecules and therapeutic compounds directly to cancerous tissues. PMID:23240070

  20. The perivascular niche regulates breast tumour dormancy.

    PubMed

    Ghajar, Cyrus M; Peinado, Héctor; Mori, Hidetoshi; Matei, Irina R; Evason, Kimberley J; Brazier, Hélène; Almeida, Dena; Koller, Antonius; Hajjar, Katherine A; Stainier, Didier Y R; Chen, Emily I; Lyden, David; Bissell, Mina J

    2013-07-01

    In a significant fraction of breast cancer patients, distant metastases emerge after years or even decades of latency. How disseminated tumour cells (DTCs) are kept dormant, and what wakes them up, are fundamental problems in tumour biology. To address these questions, we used metastasis assays in mice and showed that dormant DTCs reside on microvasculature of lung, bone marrow and brain. We then engineered organotypic microvascular niches to determine whether endothelial cells directly influence breast cancer cell (BCC) growth. These models demonstrated that endothelial-derived thrombospondin-1 induces sustained BCC quiescence. This suppressive cue was lost in sprouting neovasculature; time-lapse analysis showed that sprouting vessels not only permit, but accelerate BCC outgrowth. We confirmed this surprising result in dormancy models and in zebrafish, and identified active TGF-β1 and periostin as tumour-promoting factors derived from endothelial tip cells. Our work reveals that stable microvasculature constitutes a dormant niche, whereas sprouting neovasculature sparks micrometastatic outgrowth. PMID:23728425

  1. Tumour Angiogenesis and Angiogenic Inhibitors: A Review

    PubMed Central

    Yadav, Lalita; Puri, Naveen; Satpute, Pranali; Sharma, Vandana

    2015-01-01

    Angiogenesis is a complex process depending on the coordination of many regulators and there by activating angiogenic switch. Recent advances in understanding of angiogenic mechanism have lead to the development of several anti-angiogenic and anti-metastatic agents that use the strategy of regulation of angiogenic switch. Antiangiogenic therapy is a form of treatment not cure for cancer and represents a highly effective strategy for destroying tumour because vascular supply is the fundamental requirement for growth of tumour. Because of the quiescent nature of normal adult vasculature, angiogenic inhibitors are expected to confer a degree of specificity when compared to nonspecific modalities of chemo and radiotherapy, so it has the advantage of less toxicities, does not induce drug resistance and deliver a relatively non toxic, long term treatment of tumour. PMID:26266204

  2. Fatty tumours of the uterus.

    PubMed Central

    Pounder, D J

    1982-01-01

    Uterine fatty tumours (UFT) are uncommon and have received little attention in the English literature. They have aroused interest as a consequence of occasional diagnostic confusion with sarcomas and the continuing unresolved dispute as to their histogenesis. Three cases of UFT are described and the pathological features of note discussed. The viewpoint that these tumours are hamartomas/choristomas is rejected. UFT most probably represent tumour metaplasia within a leiomyoma. There is no uniform accepted nomenclature for such tumours and it is suggested that they be designated "uterine fatty tumours" and subdivided into "lipoma" and "mixed lipoma/leiomyoma" (synonym lipoleiomyoma). Images PMID:7174848

  3. LETTER TO THE EDITOR: Tumour anti-vascular alpha therapy: a mechanism for the regression of solid tumours in metastatic cancer

    NASA Astrophysics Data System (ADS)

    Allen, Barry J.; Raja, Chand; Rizvi, Syed; Song, Emma Y.; Graham, Peter

    2007-07-01

    Targeted alpha therapy (TAT) is an emerging therapeutic modality, thought to be best suited to cancer micrometastases, leukaemia and lymphoma. TAT has not been indicated for solid tumours. However, several melanoma patients in a phase 1 clinical trial of systemic targeted alpha therapy for melanoma experienced marked regression of subcutaneous and internal tumours. This response cannot be ascribed to killing of all cancer cells in the tumours by targeted alpha therapy. These new observations support the original hypothesis that tumours can be regressed by a mechanism called tumour anti-vascular alpha therapy. This effect depends on the expression of targeted receptors by capillary pericytes and contiguous cancer cells, and on the short-range and high-energy transfer of alpha radiation.

  4. The Tumour Microenvironment after Radiotherapy: Mechanisms of Resistance and Recurrence

    PubMed Central

    Barker, Holly E.; Paget, James T. E.; Khan, Aadil A.; Harrington, Kevin J.

    2016-01-01

    Radiotherapy plays a central part in curing cancer. For decades, most research on improving treatment outcomes has focussed on modulating radiation-induced biological effects on cancer cells. Recently, we have better understood that components within the tumour microenvironment have pivotal roles in determining treatment outcomes. In this Review, we describe vascular, stromal and immunological changes induced in the tumour microenvironment by irradiation and discuss how they may promote radioresistance and tumour recurrence. Subsequently, we highlight how this knowledge is guiding the development of new treatment paradigms in which biologically targeted agents will be combined with radiotherapy. PMID:26105538

  5. The tumour microenvironment after radiotherapy: mechanisms of resistance and recurrence.

    PubMed

    Barker, Holly E; Paget, James T E; Khan, Aadil A; Harrington, Kevin J

    2015-07-01

    Radiotherapy plays a central part in curing cancer. For decades, most research on improving treatment outcomes has focused on modulating radiation-induced biological effects on cancer cells. Recently, we have better understood that components within the tumour microenvironment have pivotal roles in determining treatment outcomes. In this Review, we describe vascular, stromal and immunological changes that are induced in the tumour microenvironment by irradiation and discuss how these changes may promote radioresistance and tumour recurrence. We also highlight how this knowledge is guiding the development of new treatment paradigms in which biologically targeted agents will be combined with radiotherapy. PMID:26105538

  6. Tumour biology: Herceptin acts as an anti-angiogenic cocktail

    NASA Astrophysics Data System (ADS)

    Izumi, Yotaro; Xu, Lei; di Tomaso, Emmanuelle; Fukumura, Dai; Jain, Rakesh K.

    2002-03-01

    Malignant tumours secrete factors that enable them to commandeer their own blood supply (angiogenesis), and blocking the action of these factors can inhibit tumour growth. But because tumours may become resistant to treatments that target individual angiogenic factors by switching over to other angiogenic molecules, a cocktail of multiple anti-angiogenic agents should be more effective. Here we show that herceptin, a monoclonal antibody against the cell-surface receptor HER2 (for human epidermal growth factor receptor-2; ref. 4), induces normalization and regression of the vasculature in an experimental human breast tumour that overexpresses HER2 in mice, and that it works by modulating the effects of different pro- and anti-angiogenic factors. As a single agent that acts against multiple targets, herceptin, or drugs like it, may offer a simple alternative to combination anti-angiogenic treatments.

  7. Target Assembly to Check Boresight Alignment of Active Sensors

    NASA Technical Reports Server (NTRS)

    Ramos-Izquierdo, Luis; Scott, V. Stanley; Riris, Haris; Cavanaugh, John; Liiva, Peter; Rodriguez, Michael

    2011-01-01

    A compact and portable target assembly (Fig. 1) has been developed to measure the boresite alignment of LRO's Lunar Orbiter Laser Altimeter (LOLA) instrument at the spacecraft level. The concept for this target assembly has evolved over many years with earlier versions used to test the Mars Observer Laser Altimeter (MOLA), the Geoscience Laser Altimeter System (GLAS), and the Mercury Laser Altimeter (MLA) space-based instruments.

  8. Ionizing Radiation Activates AMP-Activated Kinase (AMPK): A Target for Radiosensitization of Human Cancer Cells

    SciTech Connect

    Sanli, Toran; Rashid, Ayesha; Liu Caiqiong

    2010-09-01

    Purpose: Adenosine monophosphate (AMP)-activated kinase (AMPK) is a molecular energy sensor regulated by the tumor suppressor LKB1. Starvation and growth factors activate AMPK through the DNA damage sensor ataxia-telangiectasia mutated (ATM). We explored the regulation of AMPK by ionizing radiation (IR) and its role as a target for radiosensitization of human cancer cells. Methods and Materials: Lung, prostate, and breast cancer cells were treated with IR (2-8 Gy) after incubation with either ATM or AMPK inhibitors or the AMPK activator metformin. Then, cells were subjected to either lysis and immunoblotting, immunofluorescence microscopy, clonogenic survival assays, or cell cycle analysis. Results: IR induced a robust phosphorylation and activation of AMPK in all tumor cells, independent of LKB1. IR activated AMPK first in the nucleus, and this extended later into cytoplasm. The ATM inhibitor KU-55933 blocked IR activation of AMPK. AMPK inhibition with Compound C or anti-AMPK {alpha} subunit small interfering RNA (siRNA) blocked IR induction of the cell cycle regulators p53 and p21{sup waf/cip} as well as the IR-induced G2/M arrest. Compound C caused resistance to IR, increasing the surviving fraction after 2 Gy, but the anti-diabetic drug metformin enhanced IR activation of AMPK and lowered the surviving fraction after 2 Gy further. Conclusions: We provide evidence that IR activates AMPK in human cancer cells in an LKB1-independent manner, leading to induction of p21{sup waf/cip} and regulation of the cell cycle and survival. AMPK appears to (1) participate in an ATM-AMPK-p21{sup waf/cip} pathway, (2) be involved in regulation of the IR-induced G2/M checkpoint, and (3) may be targeted by metformin to enhance IR responses.

  9. Oxidative stress parameters in bitches with mammary gland tumours.

    PubMed

    Szczubiał, M; Kankofer, M; Łopuszyński, W; Dabrowski, R; Lipko, J

    2004-01-01

    The aim of the present study was to describe some of the oxidative stress parameters in bitches suffering from spontaneously occurring mammary gland tumours. The experiment involved 28 bitches which had mammary gland tumours removed surgically (15 bitches with malignant tumour and 13 with benign tumour) as well as 10 clinically healthy bitches. The activities of glutathione peroxidase (GSH-Px) and superoxide dismutase (SOD) were determined in haemolysates of erythrocytes derived from the animals. The concentrations of thiobarbituric acid reactive substances (TBARS), as well as -SH groups, were determined in blood plasma. GSH-Px activity was significantly higher in the malignant tumour group than in healthy animals. SOD activity was significantly higher in animals with tumours compared with the control group. Activities of both enzymes were higher in animals with malignant tumours than in benign groups, but the differences were not statistically significant. The concentrations of TBARS and -SH groups were similar in all examined groups. The increase of antioxidative enzyme activities in these animals may suggest the activation of antioxidative defence mechanisms in mammary gland carcinogenesis. Moreover, it might indicate the participation of oxidative stress in malignancies. Further experiments involving more animals, with more frequent sample collection and the use of other oxidative stress markers are necessary. PMID:15533114

  10. Glomus tumour of the stomach.

    PubMed

    Troller, Rebekka; Soll, Christopher; Breitenstein, Stefan

    2016-01-01

    Glomus tumours are benign tumours typically arising from the glomus bodies and primarily found under the fingernails or toenails. These rare neoplasms account for <2% of all soft tissue tumours and are generally not found in the gastrointestinal tract. We report a case of a 40-year-old man presenting with recurrent epigastric pain and pyrosis. Endoscopy revealed a solitary tumour in the antrum of the stomach. Fine-needle aspiration biopsy was suspicious for a gastrointestinal stroma tumour. After CT indicated the resectability of the tumour, showing neither lymphatic nor distant metastases, a laparoscopic-assisted gastric wedge resection was performed. Surprisingly, histology revealed a glomus tumour of the stomach. PMID:27343282

  11. Induction of IL-25 secretion from tumour-associated fibroblasts suppresses mammary tumour metastasis.

    PubMed

    Yin, Shu-Yi; Jian, Feng-Yin; Chen, Yung-Hsiang; Chien, Shih-Chang; Hsieh, Mao-Chih; Hsiao, Pei-Wen; Lee, Wen-Hwa; Kuo, Yueh-Hsiung; Yang, Ning-Sun

    2016-01-01

    Tumour-associated fibroblasts (TAFs), as a functionally supportive microenvironment, play an essential role in tumour progression. Here we investigate the role of IL-25, an endogenous anticancer factor secreted from TAFs, in suppression of mouse 4T1 mammary tumour metastasis. We show that a synthetic dihydrobenzofuran lignan (Q2-3), the dimerization product of plant caffeic acid methyl ester, suppresses 4T1 metastasis by increasing fibroblastic IL-25 activity. The secretion of IL-25 from treated human or mouse fibroblasts is enhanced in vitro, and this activity confers a strong suppressive effect on growth activity of test carcinoma cells. Subsequent in vivo experiments showed that the anti-metastatic effects of Q2-3 on 4T1 and human MDA-MD-231 tumour cells are additive when employed in combination with the clinically used drug, docetaxel. Altogether, our findings reveal that the release of IL-25 from TAFs may serve as a check point for control of mammary tumour metastasis and that phytochemical Q2-3 can efficiently promote such anticancer activities. PMID:27089063

  12. Induction of IL-25 secretion from tumour-associated fibroblasts suppresses mammary tumour metastasis

    PubMed Central

    Yin, Shu-Yi; Jian, Feng-Yin; Chen, Yung-Hsiang; Chien, Shih-Chang; Hsieh, Mao-Chih; Hsiao, Pei-Wen; Lee, Wen-Hwa; Yang, Ning-Sun

    2016-01-01

    Tumour-associated fibroblasts (TAFs), as a functionally supportive microenvironment, play an essential role in tumour progression. Here we investigate the role of IL-25, an endogenous anticancer factor secreted from TAFs, in suppression of mouse 4T1 mammary tumour metastasis. We show that a synthetic dihydrobenzofuran lignan (Q2-3), the dimerization product of plant caffeic acid methyl ester, suppresses 4T1 metastasis by increasing fibroblastic IL-25 activity. The secretion of IL-25 from treated human or mouse fibroblasts is enhanced in vitro, and this activity confers a strong suppressive effect on growth activity of test carcinoma cells. Subsequent in vivo experiments showed that the anti-metastatic effects of Q2-3 on 4T1 and human MDA-MD-231 tumour cells are additive when employed in combination with the clinically used drug, docetaxel. Altogether, our findings reveal that the release of IL-25 from TAFs may serve as a check point for control of mammary tumour metastasis and that phytochemical Q2-3 can efficiently promote such anticancer activities. PMID:27089063

  13. From sewer to saviour - targeting the lymphatic system to promote drug exposure and activity.

    PubMed

    Trevaskis, Natalie L; Kaminskas, Lisa M; Porter, Christopher J H

    2015-11-01

    The lymphatic system serves an integral role in fluid homeostasis, lipid metabolism and immune control. In cancer, the lymph nodes that drain solid tumours are a primary site of metastasis, and recent studies have suggested intrinsic links between lymphatic function, lipid deposition, obesity and atherosclerosis. Advances in the current understanding of the role of the lymphatics in pathological change and immunity have driven the recognition that lymph-targeted delivery has the potential to transform disease treatment and vaccination. In addition, the design of lymphatic delivery systems has progressed from simple systems that rely on passive lymphatic access to sophisticated structures that use nanotechnology to mimic endogenous macromolecules and lipid conjugates that 'hitchhike' onto lipid transport processes. Here, we briefly summarize the lymphatic system in health and disease and the varying mechanisms of lymphatic entry and transport, as well as discussing examples of lymphatic delivery that have enhanced therapeutic utility. We also outline future challenges to effective lymph-directed therapy. PMID:26471369

  14. Management of Gastrointestinal Stromal Tumour: Current Practices and Visions for the Future.

    PubMed

    Blay, Jean-Yves; Casali, Paolo G; Dei Tos, Angelo Paolo; Le Cesne, Axel; Reichardt, Peter

    2015-01-01

    Gastrointestinal stromal tumour (GIST), while relatively rare, is the most common mesenchymal tumour of the gastrointestinal tract. These tumours are largely resistant to cytotoxic chemotherapy and, in the past, were typically managed surgically. However, as a result of the identification of activating mutations in the proto-oncogene KIT and the development of compounds that inhibit the KIT receptor tyrosine kinase, GISTs have, in the last 14 years, become the archetype of a targeted agent-responsive tumour. Due to the almost continual emergence of new data from clinical trials and other studies on GIST diagnosis and treatment, the management of this disease requires regular review. The 2013 ArcheoloGIST summit was convened in Prague, Czech Republic. Interaction between attending physicians and the expert faculty was a core component of the summit. The current article is based on discussions held during two interactive sessions at ArcheoloGIST 2013 in which the authors aimed to: (1) reach a consensus on the current management of GIST and (2) provide a vision for the future diagnosis and treatment of this disease. PMID:25720422

  15. Analysis of nanoparticle delivery to tumours

    NASA Astrophysics Data System (ADS)

    Wilhelm, Stefan; Tavares, Anthony J.; Dai, Qin; Ohta, Seiichi; Audet, Julie; Dvorak, Harold F.; Chan, Warren C. W.

    2016-05-01

    Targeting nanoparticles to malignant tissues for improved diagnosis and therapy is a popular concept. However, after surveying the literature from the past 10 years, only 0.7% (median) of the administered nanoparticle dose is found to be delivered to a solid tumour. This has negative consequences on the translation of nanotechnology for human use with respect to manufacturing, cost, toxicity, and imaging and therapeutic efficacy. In this article, we conduct a multivariate analysis on the compiled data to reveal the contributions of nanoparticle physicochemical parameters, tumour models and cancer types on the low delivery efficiency. We explore the potential causes of the poor delivery efficiency from the perspectives of tumour biology (intercellular versus transcellular transport, enhanced permeability and retention effect, and physicochemical-dependent nanoparticle transport through the tumour stroma) as well as competing organs (mononuclear phagocytic and renal systems) and present a 30-year research strategy to overcome this fundamental limitation. Solving the nanoparticle delivery problem will accelerate the clinical translation of nanomedicine.

  16. Identification of orthologous target pairs with shared active compounds and comparison of organism-specific activity patterns.

    PubMed

    Dimova, Dilyana; Stumpfe, Dagmar; Bajorath, Jürgen

    2015-11-01

    A systematic search for active small molecules shared by orthologous targets was carried out, leading to the identification of 803 compound-based orthologous target pairs covering a total of 938 orthologues, 358 unique targets and 98 organisms. Many orthologous target pairs were found to have substantial compound coverage, enabling the introduction of an orthologous target pairs classification including 'organism cliffs' and 'potency-retaining' pairs. A total of 158 orthologous target pairs involving human orthologues were identified, which were typically associated with drug discovery-relevant targets, organism combinations and compound data. Orthologous target pairs with human orthologues included 83 potency-retaining orthologous target pairs covering a variety of targets and organisms. On the basis of these orthologous target pairs, the compound search was further extended and 1149 potent compounds were identified that only had reported activities for non-human orthologues of 48 therapeutic targets, but not their human counterparts, hence providing a large pool of candidate compounds for further evaluation. The complete set of orthologous target pairs identified in our analysis, the orthologous target pairs classification including associated data and all candidate compounds are made freely available. PMID:25931211

  17. Natural killer group 2D and CD28 receptors differentially activate mammalian/mechanistic target of rapamycin to alter murine effector CD8+ T-cell differentiation.

    PubMed

    McQueen, Bryan; Trace, Kelsey; Whitman, Emily; Bedsworth, Taylor; Barber, Amorette

    2016-03-01

    Memory CD8+ T cells are an essential component of anti-tumour and anti-viral immunity. Activation of the mammalian/mechanistic target of rapamycin (mTOR) pathway has been implicated in regulating the differentiation of effector and memory T cells. However, the mechanisms that control mTOR activity during immunity to tumours and infections are not well known. Activation of co-stimulatory receptors, including CD28 and natural killer group 2D (NKG2D), activate phosphatidylinositol-3 kinase and subsequently may activate the mTOR pathway in CD8+ T cells. This study compared the activation of the mTOR signalling pathway after co-stimulation through CD28 or NKG2D receptors in murine effector CD8+ T cells. Compared with CD28 co-stimulation, activation through CD3 and NKG2D receptors had weaker activation of mTORc1, as shown by decreased phosphorylation of mTORc1 targets S6K1, ribosomal protein S6 and eukaryotic initiation factor 4E binding protein 1. NKG2D co-stimulation also showed increased gene expression of tuberous sclerosis protein 2, a negative regulator of mTORc1, whereas CD28 co-stimulation increased gene expression of Ras homologue enriched in brain, an activator of mTORc1, and hypoxia-inducible factor-1α and vascular endothelial growth factor-α, pro-angiogenic factors downstream of mTORc1. Strong mTORc1 activation in CD28-co-stimulated cells also increased expression of transcription factors that support effector cell differentiation, namely T-bet, B lymphocyte-induced maturation protein (BLIMP-1), interferon regulatory factor 4, and inhibitor of DNA binding 2, whereas low levels of mTORc1 activation allowed for the expression of Eomes, B-cell lymphoma 6 (BCL6), and inhibitor of DNA binding 3 during NKG2D stimulation, and increased expression of memory markers CD62 ligand and CD127. These data show that compared with CD28, co-stimulation through the NKG2D receptor leads to the differential activation of the mTOR signalling pathway and potentially supports

  18. GSK621 Targets Glioma Cells via Activating AMP-Activated Protein Kinase Signalings

    PubMed Central

    Jiang, Hong; Liu, Wei; Zhan, Shi-Kun; Pan, Yi-Xin; Bian, Liu-Guan; Sun, Bomin; Sun, Qing-Fang; Pan, Si-Jian

    2016-01-01

    Here, we studied the anti-glioma cell activity by a novel AMP-activated protein kinase (AMPK) activator GSK621. We showed that GSK621 was cytotoxic to human glioma cells (U87MG and U251MG lines), possibly via provoking caspase-dependent apoptotic cell death. Its cytotoxicity was alleviated by caspase inhibitors. GSK621 activated AMPK to inhibit mammalian target of rapamycin (mTOR) and downregulate Tetraspanin 8 (Tspan8) in glioma cells. AMPK inhibition, through shRNA knockdown of AMPKα or introduction of a dominant negative (T172A) AMPKα, almost reversed GSK621-induced AMPK activation, mTOR inhibition and Tspan8 degradation. Consequently, GSK621’s cytotoxicity in glioma cells was also significantly attenuated by AMPKα knockdown or mutation. Further studies showed that GSK621, at a relatively low concentration, significantly potentiated temozolomide (TMZ)’s sensitivity and lethality against glioma cells. We summarized that GSK621 inhibits human glioma cells possibly via activating AMPK signaling. This novel AMPK activator could be a novel and promising anti-glioma cell agent. PMID:27532105

  19. Immune activation by combination human lymphokine-activated killer and dendritic cell therapy

    PubMed Central

    West, E J; Scott, K J; Jennings, V A; Melcher, A A

    2011-01-01

    Background: Optimal cellular immunotherapy for cancer should ideally harness both the innate and adaptive arms of the immune response. Lymphokine-activated killer cells (LAKs) can trigger early innate killing of tumour targets, whereas long-term adaptive-specific tumour control requires priming of CD8+ cytotoxic lymphocytes (CTLs) following acquisition of tumour-associated antigens (TAAs) by antigen-presenting cells such as dendritic cells (DCs). As DCs stimulate both innate and adaptive effectors, combination cell therapy using LAKs and DCs has the potential to maximise anti-tumour immune priming. Methods: Reciprocal activation between human clinical grade LAKs and DCs on co-culture, and its immune consequences, was monitored by cell phenotype, cytokine release and priming of both innate and adaptive cytotoxicity against melanoma targets. Results: Co-culture of DCs and LAKs led to phenotypic activation of natural killer (NK) cells within the LAK population, which was associated with increased production of inflammatory cytokines and enhanced innate cytotoxicity against tumour cell targets. The LAKs reciprocally matured DCs, and the combination of LAKs and DCs, on addition of melanoma cells, supported priming of specific anti-tumour CTLs better than DCs alone. Conclusion: Clinical-grade LAKs/DCs represents a practical, effective combination cell immunotherapy for stimulation of both innate and adaptive anti-tumour immunity in cancer patients. PMID:21847125

  20. Borderline ovarian tumours.

    PubMed

    Tropé, Claes Göran; Kaern, Janne; Davidson, Ben

    2012-06-01

    Borderline ovarian tumours account for 10-20% of all epithelial ovarian cancer. Historically, standard primary surgery has included borderline ovarian tumours, omentectomy, peritoneal washing and multiple biopsies. As one-third of borderline ovarian tumours are diagnosed in women under the age of 40 years, fertility-sparing treatment has been more frequently used in the past 10 years. Fertility drugs are well tolerated in women with infertility after fertility-sparing surgery. Careful selection of candidates is necessary. Laparoscopic techniques can be used, but should be reserved for oncologic surgeons. This conservative treatment increases the rate of recurrence, albeit with no effect on survival. The pregnancy rate is nearly 50%, and most are achieved spontaneously. These women should be closely followed up. The question is whether this is acceptable from a gynaecologic oncologic point of view. For this reason, we will discuss recently published studies and gynaecologic oncologic concerns about the mode of fertility-sparing surgery and its consequences. PMID:22321906

  1. Tumours of the kidney

    PubMed Central

    Nielsen, Svend W.; Mackey, L. J.; Misdorp, W.

    1976-01-01

    The most frequent renal tumours of animals are renal cell carcinoma and nephroblastoma. Renal cell carcinomas are seen mainly in dogs and cattle and nephroblastoma is encountered in pigs, puppies, and calves. Renal cell carcinomas are usually papillary in the dog. They show a marked propensity for vascular invasion, penetration of the posterior vena cava, and subsequent pulmonary metastasis. Nephroblastoma, which is morphologically identical to Wilms' tumour of children, is almost always a benign tumour in animals. It is one of the most frequent neoplasms of pigs, possibly owing to the fact that most pigs are slaughtered (and examined) when a few months old. Lymphosarcoma involving the kidney is particularly frequent in the cat, but is also seen in other species as part of a generalized disease. ImagesFig. 5,6Fig. 7Fig. 8Fig. 1,2Fig. 3,4Fig. 16,17,18,19Fig. 9,10Fig. 11Fig. 12Fig. 13Fig. 14,15 PMID:1086154

  2. High frequency of tumours in Mulibrey nanism.

    PubMed

    Karlberg, Niklas; Karlberg, Susann; Karikoski, Riitta; Mikkola, Sakari; Lipsanen-Nyman, Marita; Jalanko, Hannu

    2009-06-01

    Mulibrey nanism (MUL) is a monogenic disorder with prenatal-onset growth failure, typical clinical characteristics, cardiopathy and tendency for a metabolic syndrome. It is caused by recessive mutations in the TRIM37 gene encoding for the peroxisomal TRIM37 protein with ubiquitin-ligase activity. In this work, the frequency and pathology of malignant and benign tumours were analysed in a national cohort of 89 Finnish MUL patients aged 0.7-76 years. The subjects had a clinical and radiological evaluation, and histological and immunohistocemical analyses on specimens obtained from biopsy, surgery or autopsy, were performed. The results show that the MUL patients have disturbed architecture with ectopic tissues and a high frequency of both benign and malignant tumours detectable in several internal organs. A total of 210 tumorous lesions were detected in 66/89 patients (74%). Fifteen malignancies occurred in 13 patients (15%), seven of them in the kidney (five Wilms' tumours), three in the thyroid gland, two gynaecological cancers, one gastrointestinal carcinoid tumour, one neuropituitary Langerhans cell histiocytosis and one case of acute lymphoblastic leukaemia (ALL). Tumours detected by radiology in the liver and other organs mainly comprised strongly dilated blood vessels (peliosis), vascularized cysts and nodular lesions. The lesions showed strong expression of the endothelial cell markers CD34 and CD31 as well as the myocyte marker alpha-smooth muscle actin (alpha-SMA). Our findings show that MUL is associated with frequent malignant tumours and benign adenomatous and vascular lesions, as well as disturbed organ development. PMID:19334051

  3. Therapeutic effects of date fruits (Phoenix dactylifera) in the prevention of diseases via modulation of anti-inflammatory, anti-oxidant and anti-tumour activity

    PubMed Central

    Rahmani, Arshad H; Aly, Salah M; Ali, Habeeb; Babiker, Ali Y; Srikar, Sauda; khan, Amjad A

    2014-01-01

    The current mode of treatment of various diseases based on synthetic drugs is expensive, alters genetic and metabolic pathways and also shows adverse side effects. Thus, safe and effective approach is needed to prevent the diseases development and progression. In this vista, Natural products are good remedy in the treatment/management of diseases and they are affordable and effective without any adverse effects. Dates are main fruit in the Arabian Peninsula and are considered to be one of the most significant commercial crops and also have been documented in Holy Quran and modern scientific literatures. Earlier studies have shown that constituents of dates act as potent antioxidant, anti-tumour as well as anti-inflammatory, provide a suitable alternative therapy in various diseases cure. In this review, dates fruits has medicinal value are summarized in terms of therapeutic implications in the diseases control through anti-oxidant, anti-inflammatory, anti-tumour and ant-diabetic effect. PMID:24753740

  4. A novel role for the tumour suppressor Nitrilase1 modulating the Wnt/β-catenin signalling pathway.

    PubMed

    Mittag, Sonnhild; Valenta, Tomas; Weiske, Jörg; Bloch, Laura; Klingel, Susanne; Gradl, Dietmar; Wetzel, Franziska; Chen, Yuan; Petersen, Iver; Basler, Konrad; Huber, Otmar

    2016-01-01

    Nitrilase1 was classified as a tumour suppressor in association with the fragile histidine-triad protein Fhit. However, knowledge about nitrilase1 and its tumour suppressor function is still limited. Whereas nitrilase1 and Fhit are discrete proteins in mammals, they are merged in Drosophila melanogaster and Caenorhabditis elegans. According to the Rosetta-Stone hypothesis, proteins encoded as fusion proteins in one organism and as separate proteins in another organism may act in the same signalling pathway. Although a direct interaction of human nitrilase1 and Fhit has not been shown, our previous finding that Fhit interacts with β-catenin and represses its transcriptional activity in the canonical Wnt pathway suggested that human nitrilase1 also modulates Wnt signalling. In fact, human nitrilase1 forms a complex with β-catenin and LEF-1/TCF-4, represses β-catenin-mediated transcription and shows an additive effect together with Fhit. Knockdown of human nitrilase1 enhances Wnt target gene expression. Moreover, our experiments show that β-catenin competes away human nitrilase1 from LEF-1/TCF and thereby contributes to the activation of Wnt-target gene transcription. Inhibitory activity of human nitrilase1 on vertebrate Wnt signalling was confirmed by repression of Wnt-induced double axis formation in Xenopus embryogenesis. In line with this finding, the Drosophila fusion protein Drosophila NitFhit directly binds to Armadillo and represses the Wingless pathway in reporter gene assays. Genetic experiments confirmed the repressive activity of Drosophila NitFhit on Wingless signalling in the Drosophila wing imaginal disc. In addition, colorectal tumour microarray analysis revealed a significantly reduced expression of human nitrilase1 in poorly differentiated tumours. Taken together, repression of the canonical Wnt pathway represents a new mechanism for the human nitrilase1 tumour suppressor function. PMID:27462437

  5. A novel role for the tumour suppressor Nitrilase1 modulating the Wnt/β-catenin signalling pathway

    PubMed Central

    Mittag, Sonnhild; Valenta, Tomas; Weiske, Jörg; Bloch, Laura; Klingel, Susanne; Gradl, Dietmar; Wetzel, Franziska; Chen, Yuan; Petersen, Iver; Basler, Konrad; Huber, Otmar

    2016-01-01

    Nitrilase1 was classified as a tumour suppressor in association with the fragile histidine-triad protein Fhit. However, knowledge about nitrilase1 and its tumour suppressor function is still limited. Whereas nitrilase1 and Fhit are discrete proteins in mammals, they are merged in Drosophila melanogaster and Caenorhabditis elegans. According to the Rosetta-Stone hypothesis, proteins encoded as fusion proteins in one organism and as separate proteins in another organism may act in the same signalling pathway. Although a direct interaction of human nitrilase1 and Fhit has not been shown, our previous finding that Fhit interacts with β-catenin and represses its transcriptional activity in the canonical Wnt pathway suggested that human nitrilase1 also modulates Wnt signalling. In fact, human nitrilase1 forms a complex with β-catenin and LEF-1/TCF-4, represses β-catenin-mediated transcription and shows an additive effect together with Fhit. Knockdown of human nitrilase1 enhances Wnt target gene expression. Moreover, our experiments show that β-catenin competes away human nitrilase1 from LEF-1/TCF and thereby contributes to the activation of Wnt-target gene transcription. Inhibitory activity of human nitrilase1 on vertebrate Wnt signalling was confirmed by repression of Wnt-induced double axis formation in Xenopus embryogenesis. In line with this finding, the Drosophila fusion protein Drosophila NitFhit directly binds to Armadillo and represses the Wingless pathway in reporter gene assays. Genetic experiments confirmed the repressive activity of Drosophila NitFhit on Wingless signalling in the Drosophila wing imaginal disc. In addition, colorectal tumour microarray analysis revealed a significantly reduced expression of human nitrilase1 in poorly differentiated tumours. Taken together, repression of the canonical Wnt pathway represents a new mechanism for the human nitrilase1 tumour suppressor function. PMID:27462437

  6. Maspin as a Tumour Suppressor in Salivary Gland Tumour

    PubMed Central

    Ashok, Nipun; Sheirawan, Mohammad Kinan; Altamimi, Mohammed Alsakran; Alenzi, Faris; Azzeghaiby, Saleh Nasser; Baroudi, Kusai; Nassani, Mohammad Zakaria

    2014-01-01

    Maspin is a protein that belongs to serin protease inhibitor (serpin) superfamily. The purpose of this study was to review the literature concerning the expression of maspin in salivary gland tumours. A literature search was done using MEDLINE, accessed via the National Library of Medicine PubMed interface. Statistical analysis was not done because only seven studies were available in literature, the collected data were different and the results could not be compared. Expression of maspin was down regulated in more aggressive salivary gland tumours. Maspin may function as a tumour suppressor in salivary gland tumours. PMID:25654053

  7. Selective Activation of Neuronal Targets With Sinusoidal Electric Stimulation

    PubMed Central

    Freeman, Daniel K.; Eddington, Donald K.; Rizzo, Joseph F.

    2010-01-01

    Electric stimulation of the CNS is being evaluated as a treatment modality for a variety of neurological, psychiatric, and sensory disorders. Despite considerable success in some applications, existing stimulation techniques offer little control over which cell types or neuronal substructures are activated by stimulation. The ability to more precisely control neuronal activation would likely improve the clinical outcomes associated with these applications. Here, we show that specific frequencies of sinusoidal stimulation can be used to preferentially activate certain retinal cell types: photoreceptors are activated at 5 Hz, bipolar cells at 25 Hz, and ganglion cells at 100 Hz. In addition, low-frequency stimulation (≤25 Hz) did not activate passing axons but still elicited robust synaptically mediated responses in ganglion cells; therefore, elicited neural activity is confined to within a focal region around the stimulating electrode. Our results suggest that sinusoidal stimulation provides significantly improved control over elicited neural activity relative to conventional pulsatile stimulation. PMID:20810683

  8. Nonimaging active system determination of target shape through turbulent medium

    NASA Astrophysics Data System (ADS)

    Chandler, Susan M.; Lukesh, Gordon W.

    2001-01-01

    Image reconstruction techniques for atmospheric applications often work best with an initial estimate of the object support. This paper examines the ability of a non-imaging laser pointing system to obtain an estimate of target size and shape based on the statistics of the return signal. Fundamental limits on system pointing, such as the tracking errors, corrupt a simple raster scan that would provide gross object shape form the convolution of the far-field pattern with the target. Using techniques developed previously for the estimation of pointing performance, it is possible to distinguish between simple shapes such as bars, circles and T's based on the statistics of the received time signal. Simulated space objects, such as those illuminated during field experiments, may also be distinguished.

  9. Oxidative stress, polarization of macrophages and tumour angiogenesis: Efficacy of caffeic acid.

    PubMed

    Oršolić, Nada; Kunštić, Martina; Kukolj, Marina; Gračan, Romana; Nemrava, Johann

    2016-08-25

    Macrophage polarization is a process when macrophage expresses different functional programs in response to microenvironmental signals and two extreme forms exist; M1 and M2 macrophages. M1 macrophages are highly microbicidal and anticancer with enhanced ability to kill and phagocytose pathogens, upregulate pro-inflammatory cytokines and reactive molecular species, and present antigens; M2 macrophages and the related tumour associated macrophages (TAMs) regulate tissue remodelling and promote tissue repair and angiogenesis and can amplification of metabolic pathways that can suppress adaptive immune responses. It is demonstrated that ROS production, critical for the activation and functions of M1 macrophages, is necessary for the differentiation of M2 macrophages and TAMs, and that antioxidant therapy blocks TAMs differentiation and tumorigenesis in mouse models of cancer. In order to study how caffeic acid (CA), a natural antioxidant, affects macrophage function, polarization, angiogenesis and tumour growth we injected mice with Ehrlich ascites tumour (EAT) cells and treated them for 10 days with CA in a dose of 40 and/or 80 mg kg(-1.) Macrophage polarization was further characterized by quantifying secreted pro- and anti-inflammatory cytokines, nitric oxide and arginase 1 activity. CA may increase the cytotoxic actions of M1 macrophages and inhibit tumour growth; inhibitory activity on TAMs may be mediated through its antioxidative activity. Taken together, we conclude that the antitumour activity of CA was the result of the synergistic activities of different mechanisms by which CA acts on proliferation, angiogenesis, immunomodulation and survival. The continuous administration of CA efficiently blocked the occurrence of TAMs and markedly suppressed tumorigenesis in mouse cancer models. Targeting TAMs by antioxidants can be a potentially effective method for cancer treatment. PMID:27378625

  10. 13 CFR 124.509 - What are non-8(a) business activity targets?

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... obtain non-8(a) revenues. (e) Waiver of sole source prohibition. (1) The AA/BD, or his or her designee... activity targets? 124.509 Section 124.509 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION 8(a... Contractual Assistance § 124.509 What are non-8(a) business activity targets? (a) General. (1) To ensure...

  11. Aptamers: Active Targeting Ligands for Cancer Diagnosis and Therapy

    PubMed Central

    Wu, Xu; Chen, Jiao; Wu, Min; Zhao, Julia Xiaojun

    2015-01-01

    Aptamers, including DNA, RNA and peptide aptamers, are a group of promising recognition units that can specifically bind to target molecules and cells. Due to their excellent specificity and high affinity to targets, aptamers have attracted great attention in various fields in which selective recognition units are required. They have been used in biosensing, drug delivery, disease diagnosis and therapy (especially for cancer treatment). In this review, we summarized recent applications of DNA and RNA aptamers in cancer theranostics. The specific binding ability of aptamers to cancer-related markers and cancer cells ensured their high performance for early diagnosis of cancer. Meanwhile, the efficient targeting ability of aptamers to cancer cells and tissues provided a promising way to deliver imaging agents and drugs for cancer imaging and therapy. Furthermore, with the development of nanoscience and nanotechnology, the conjugation of aptamers with functional nanomaterials paved an exciting way for the fabrication of theranostic agents for different types of cancers, which might be a powerful tool for cancer treatment. PMID:25699094

  12. Ovarian-type epithelial tumours of the testis: immunohistochemical and molecular analysis of two serous borderline tumours of the testis.

    PubMed

    Bürger, Tobias; Schildhaus, Hans-Ulrich; Inniger, Reinhard; Hansen, Joachim; Mayer, Peter; Schweyer, Stefan; Radzun, Heinz Joachim; Ströbel, Philipp; Bremmer, Felix

    2015-01-01

    Tumours of ovarian-epithelial type of the testis, including serous borderline tumours, represent very rare entities. They are identical to the surface epithelial tumours of the ovary and have been reported in patients from 14 to 68 years of age. We describe two cases of a 46- and a 39-year old man with incidental findings of intratesticular masses of the left respectively right testis. Under the assumption of a malignant testicular tumour the patients were subjected to inguinal orchiectomy. Histologically, the tumours were identical to their ovarian counterparts: They showed a cystic configuration with a fibrous wall and irregular papillary structures lined by partially multistratified columnar cells and areas of hobnail cells. Furthermore, there was mild cytological atypia with a proliferative activity of below 5% as proved by Ki67 staining; mitoses could not be detected. Immunohistochemically, the tumour cells displayed expression of pan-cytokeratin AE3, progesterone receptor, Wilms' tumour protein (WT1), and PAX8 (Paired box gene 8). Estrogen receptor was expressed in one case. Octamer-binding transcription factor-4 (OCT4), calretinin, thrombomodulin, and D2-40 were not expressed. Mutation testing of BRAF revealed a BRAF V600E mutation in one case, while testing for KRAS mutations proved to be negative in both. The BRAF mutated tumour showed strong cytosolic and membranous positivity for B-Raf also on immunohistochemical analysis. Comparative genomic hybridization of one case could not reveal any chromosomal aberrations. PMID:26197800

  13. Abnormal Ventral and Dorsal Attention Network Activity during Single and Dual Target Detection in Schizophrenia

    PubMed Central

    Jimenez, Amy M.; Lee, Junghee; Wynn, Jonathan K.; Cohen, Mark S.; Engel, Stephen A.; Glahn, David C.; Nuechterlein, Keith H.; Reavis, Eric A.; Green, Michael F.

    2016-01-01

    Early visual perception and attention are impaired in schizophrenia, and these deficits can be observed on target detection tasks. These tasks activate distinct ventral and dorsal brain networks which support stimulus-driven and goal-directed attention, respectively. We used single and dual target rapid serial visual presentation (RSVP) tasks during fMRI with an ROI approach to examine regions within these networks associated with target detection and the attentional blink (AB) in 21 schizophrenia outpatients and 25 healthy controls. In both tasks, letters were targets and numbers were distractors. For the dual target task, the second target (T2) was presented at three different lags after the first target (T1) (lag1 = 100 ms, lag3 = 300 ms, lag7 = 700ms). For both single and dual target tasks, patients identified fewer targets than controls. For the dual target task, both groups showed the expected AB effect with poorer performance at lag 3 than at lags 1 or 7, and there was no group by lag interaction. During the single target task, patients showed abnormally increased deactivation of the temporo-parietal junction (TPJ), a key region of the ventral network. When attention demands were increased during the dual target task, patients showed overactivation of the posterior intraparietal cortex, a key dorsal network region, along with failure to deactivate TPJ. Results suggest inefficient and faulty suppression of salience-oriented processing regions, resulting in increased sensitivity to stimuli in general, and difficulty distinguishing targets from non-targets. PMID:27014135

  14. Tumour Necrosis Factor Superfamily Members in the Pathogenesis of Inflammatory Bowel Disease

    PubMed Central

    Ślebioda, Tomasz J.; Kmieć, Zbigniew

    2014-01-01

    Inflammatory bowel disease (IBD) is a group of inflammatory conditions of the gastrointestinal tract of unclear aetiology of which two major forms are Crohn's disease (CD) and ulcerative colitis (UC). CD and UC are immunologically distinct, although they both result from hyperactivation of proinflammatory pathways in intestines and disruption of intestinal epithelial barrier. Members of the tumour necrosis factor superfamily (TNFSF) are molecules of broad spectrum of activity, including direct disruption of intestinal epithelial barrier integrity and costimulation of proinflammatory functions of lymphocytes. Tumour necrosis factor (TNF) has a well-established pathological role in IBD which also serves as a target in IBD treatment. In this review we discuss the role of TNF and other TNFSF members, notably, TL1A, FasL, LIGHT, TRAIL, and TWEAK, in the pathogenesis of IBD. PMID:25045210

  15. HIF1α and HIF2α: sibling rivalry in hypoxic tumour growth and progression.

    PubMed

    Keith, Brian; Johnson, Randall S; Simon, M Celeste

    2012-01-01

    Hypoxia-inducible factors (HIFs) are broadly expressed in human cancers, and HIF1α and HIF2α were previously suspected to promote tumour progression through largely overlapping functions. However, this relatively simple model has now been challenged in light of recent data from various approaches that reveal unique and sometimes opposing activities of these HIFα isoforms in both normal physiology and disease. These effects are mediated in part through the regulation of unique target genes, as well as through direct and indirect interactions with important oncoproteins and tumour suppressors, including MYC and p53. As HIF inhibitors are currently undergoing clinical evaluation as cancer therapeutics, a more thorough understanding of the unique roles performed by HIF1α and HIF2α in human neoplasia is warranted. PMID:22169972

  16. Melanoma miRNA trafficking controls tumour primary niche formation.

    PubMed

    Dror, Shani; Sander, Laureen; Schwartz, Hila; Sheinboim, Danna; Barzilai, Aviv; Dishon, Yuval; Apcher, Sebastien; Golan, Tamar; Greenberger, Shoshana; Barshack, Iris; Malcov, Hagar; Zilberberg, Alona; Levin, Lotan; Nessling, Michelle; Friedmann, Yael; Igras, Vivien; Barzilay, Ohad; Vaknine, Hananya; Brenner, Ronen; Zinger, Assaf; Schroeder, Avi; Gonen, Pinchas; Khaled, Mehdi; Erez, Neta; Hoheisel, Jörg D; Levy, Carmit

    2016-09-01

    Melanoma originates in the epidermis and becomes metastatic after invasion into the dermis. Prior interactions between melanoma cells and dermis are poorly studied. Here, we show that melanoma cells directly affect the formation of the dermal tumour niche by microRNA trafficking before invasion. Melanocytes, cells of melanoma origin, are specialized in releasing pigment vesicles, termed melanosomes. In melanoma in situ, we found melanosome markers in distal fibroblasts before melanoma invasion. The melanosomes carry microRNAs into primary fibroblasts triggering changes, including increased proliferation, migration and pro-inflammatory gene expression, all known features of cancer-associated fibroblasts (CAFs). Specifically, melanosomal microRNA-211 directly targets IGF2R and leads to MAPK signalling activation, which reciprocally encourages melanoma growth. Melanosome release inhibitor prevented CAF formation. Since the first interaction of melanoma cells with blood vessels occurs in the dermis, our data suggest an opportunity to block melanoma invasion by preventing the formation of the dermal tumour niche. PMID:27548915

  17. The cellular adaptations to hypoxia as novel therapeutic targets in childhood cancer.

    PubMed

    Adamski, J K; Estlin, E J; Makin, G W J

    2008-05-01

    Exposure of tumour cells to reduced levels of oxygen (hypoxia) is a common finding in adult tumours. Hypoxia induces a myriad of adaptive changes within tumour cells which result in increased anaerobic glycolysis, new blood vessel formation, genetic instability and a decreased responsiveness to both radio and chemotherapy. Hypoxia correlates with disease stage and outcome in adult epithelial tumours and increasingly it is becoming apparent that hypoxia is also important in paediatric tumours. Despite its adverse effects upon tumour response to treatment hypoxia offers several avenues for new drug development. Bioreductive agents already exist, which are preferentially activated in areas of hypoxia, and thus have less toxicity for normal tissue. Additionally the adaptive cellular response to hypoxia offers several novel targets, including vascular endothelial growth factor (VEGF), carbonic anhydrase, and the central regulator of the cellular response to hypoxia, hypoxia inducible factor-1 (HIF-1). Novel agents have emerged against all of these targets and are at various stages of clinical and pre-clinical development. Hypoxia offers an exciting opportunity for new drug development that can include paediatric tumours at an early stage. PMID:18207646

  18. Mutational patterns in oncogenes and