2,230 research outputs found

    Tumor-targeting adenovirus OBP-401 inhibits primary and metastatic tumor growth of triple-negative breast cancer in orthotopic nude-mouse models.

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    Our laboratory previously developed a highly-invasive, triple-negative breast cancer (TNBC) variant using serial orthotopic implantation of the human MDA-MB-231 cell line in nude mice. The isolated variant was highly-invasive in the mammary gland and lymphatic channels and metastasized to lymph nodes in 10 of 12 mice compared to 2 of 12 of the parental cell line. In the present study, the tumor-selective telomerase dependent OBP-401 adenovirus was injected intratumorally (i.t.) (1 Ă— 108 PFU) when the high-metastatic MDA-MB-231 primary tumor expressing red fluorescent protein (MDA-MB-231-RFP) reached approximately 500 mm3 (diameter; 10 mm). The mock-infected orthotopic primary tumor grew rapidly. After i.t. OBP-401 injection, the growth of the orthotopic tumors was arrested. Six weeks after implantation, the fluorescent area and fluorescence intensity showed no increase from the beginning of treatment. OBP-401 was then injected into high-metastatic MDA-MB-231-RFP primary orthotopic tumor growing in mice which already had developed metastasis within lymphatic ducts. All 7 of 7 control mice subsequently developed lymph node metastasis. In contrast, none of 7 mice which received OBP-401 had lymph node metastasis. Seven of 7 control mice also had gross lung metastasis. In contrast, none of the 7 mice which received OBP-401 had gross lung metastasis. Confocal laser microscopy imaging demonstrated that all control mice had diffuse lung metastases. In contrast, all 7 mice which received OBP-401 only had a few metastatic cells in the lung. OBP-401 treatment significantly extended survival of the treated mice

    Fluorescence-guided surgery of a highly-metastatic variant of human triple-negative breast cancer targeted with a cancer-specific GFP adenovirus prevents recurrence.

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    We have previously developed a genetically-engineered GFP-expressing telomerase-dependent adenovirus, OBP-401, which can selectively illuminate cancer cells. In the present report, we demonstrate that targeting a triple-negative high-invasive human breast cancer, orthotopically-growing in nude mice, with OBP-401 enables curative fluorescence-guided surgery (FGS). OBP-401 enabled complete resection and prevented local recurrence and greatly inhibited lymph-node metastasis due to the ability of the virus to selectively label and subsequently kill cancer cells. In contrast, residual breast cancer cells become more aggressive after bright (white)-light surgery (BLS). OBP-401-based FGS also improved the overall survival compared with conventional BLS. Thus, metastasis from a highly-aggressive triple-negative breast cancer can be prevented by FGS in a clinically-relevant mouse model

    Adenoviral targeting of malignant melanoma for fluorescence-guided surgery prevents recurrence in orthotopic nude-mouse models.

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    Malignant melanoma requires precise resection in order to avoid metastatic recurrence. We report here that the telomerase-dependent, green fluorescent protein (GFP)-containing adenovirus OBP-401 could label malignant melanoma with GFP in situ in orthotopic mouse models. OBP-401-based fluorescence-guided surgery (FGS) resulted in the complete resection of malignant melanoma in the orthotopic models, where conventional bright-light surgery (BLS) could not. High-dose administration of OBP-401 enabled FGS without residual cancer cells or recurrence, due to its dual effect of cancer-cell labeling with GFP and killing

    Ataxia-Telangiectasia Mutated and the Mre11-Rad50-NBS1 Complex:Promising Targets for Radiosensitization

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    Radiotherapy plays a central part in cancer treatment, and use of radiosensitizing agents can greatly enhance this modality. Although studies have shown that several chemotherapeutic agents have the potential to increase the radiosensitivity of tumor cells, investigators have also studied a number of molecularly targeted agents as radiosensitizers in clinical trials based on reasonably promising preclinical data. Recent intense research into the DNA damage-signaling pathway revealed that ataxia-telangiectasia mutated (ATM) and the Mre11-Rad50-NBS1 (MRN) complex play central roles in DNA repair and cell cycle checkpoints and that these molecules are promising targets for radiosensitization. Researchers recently developed three ATM inhibitors (KU-55933, CGK733, and CP466722) and an MRN complex inhibitor (mirin) and showed that they have great potential as radiosensitizers of tumors in preclinical studies. Additionally, we showed that a telomerase-dependent oncolytic adenovirus that we developed (OBP-301 [telomelysin]) produces profound radiosensitizing effects by inhibiting the MRN complex via the adenoviral E1B55kDa protein. A recent Phase I trial in the United States determined that telomelysin was safe and well tolerated in humans, and this agent is about to be tested in combination with radiotherapy in a clinical trial based on intriguing preclinical data demonstrating that telomelysin and ionizing radiation can potentiate each other. In this review, we highlight the great potential of ATM and MRN complex inhibitors, including telomelysin, as radiosensitizing agents

    Bone and Soft-Tissue Sarcoma: A New Target for Telomerase-Specific Oncolytic Virotherapy

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    Adenovirus serotype 5 (Ad5) is widely and frequently used as a virus vector in cancer gene therapy and oncolytic virotherapy. Oncolytic virotherapy is a novel antitumor treatment for inducing lytic cell death in tumor cells without affecting normal cells. Based on the Ad5 genome, we have generated three types of telomerase-specific replication-competent oncolytic adenoviruses: OBP-301 (Telomelysin), green fluorescent protein (GFP)-expressing OBP-401 (TelomeScan), and tumor suppressor p53-armed OBP-702. These viruses drive the expression of the adenoviral E1A and E1B genes under the control of the hTERT (human telomerase reverse transcriptase-encoding gene) promoter, providing tumor-specific virus replication. This review focuses on the therapeutic potential of three hTERT promoter-driven oncolytic adenoviruses against bone and soft-tissue sarcoma cells with telomerase activity. OBP-301 induces the antitumor effect in monotherapy or combination therapy with chemotherapeutic drugs via induction of autophagy and apoptosis. OBP-401 enables visualization of sarcoma cells within normal tissues by serving as a tumor-specific labeling reagent for fluorescence-guided surgery via induction of GFP expression. OBP-702 exhibits a profound antitumor effect in OBP-301-resistant sarcoma cells via activation of the p53 signaling pathway. Taken together, telomerase-specific oncolytic adenoviruses are promising antitumor reagents that are expected to provide novel therapeutic options for the treatment of bone and soft-tissue sarcomas

    Regional and Sector Environmental Efficiency Empirical Evidence from Structural Shift-share Analysis of NAMEA data

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    This paper provides new empirical evidence on regional–national disparities in environmental efficiency, based on case studies of Italy and the Lazio region, which includes the city of Rome. Shift-share analyses provide evidence on the drivers of environmental efficiency and on sector specificity. This confirms the usefulness of this method for studying the environmental economics realm, in order to investigate structural and efficiency factors at the level of within country environmental efficiency performance, even in light of the different shares of services. Our evidence shows that although the Rome region has achieved higher environmental performance compared to Italy mainly thanks to its being less industry based, some critical points in the energy sector and in some services should be taken into account in shaping the future development of the region. Environmental, industrial and sector-oriented policy making may also derive valuable information from the evidence provided by our study.NAMEA, Shift Share, Regional Development, RAMEA, Emission Efficiency, Economic Efficiency

    Embedding the drivers of emission efficiency at regional level Analyses of NAMEA data

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    This paper provides new empirical evidence on regional-national disparities in environmental efficiency, based on analyses of NAMEA data referring to Italy and the Lazio region, where Rome is the main city. Shift-share analyses provide evidence on the drivers of environmental efficiency and on sector specificity. This confirms the usefulness of this method, in order to investigate structural and efficiency factors at the level of within country environmental efficiency performance. Our evidence shows that although the region around Rome has achieved higher environmental performance compared to Italy mainly thank to its being less industry based, some critical points in the energy sector and in some services should be taken into account in shaping the future development of the region. In addition, the use of regional NAMEA for econometric investigations of emission efficiency drivers at national level shows that though north south disparities favour northern and richer regions, in accordance with development oriented dynamics, environmental hot spots driven by specialization and efficiency related issues also appear in some northern industrial regions. Further, the role of public ad private R&D is of main relevance in enhancing emission on economic value ratios.

    Structural decomposition analysis and index number theory: an empirical application of the Montgomery decomposition.

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    Abstract In recent years a large number of empirical articles on structural decomposition analysis, which aims at disentangling an aggregate change into its factors, has been published in Economic Systems Research. Dietzenbacher and Los (D&L) proved that in case of n factors the number of possible decompositions is equal to n!, non of which satisfies time reversal. Averages of decompositions satisfy this requirement, such as the average of all decompositions. In index number theory this problem is known as the decomposition of an aggregate change into symmetric factors (usually two: price and quantity). Balk proposes to generalize the Montgomery decomposition, which obeys time reversal, to three factors. In this paper we apply this solution to a more intricate decomposition into four factors, viz. the example analyzed by D&L. We show that for most sectors the results of the Montgomery decomposition are remarkably close to those of the average of the 24 decompositions.decomposition analysis
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