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Sample records for attenuated oncolytic recombinant

  1. Highly Attenuated Recombinant Vesicular Stomatitis Virus VSV-12′GFP Displays Immunogenic and Oncolytic Activity

    Science.gov (United States)

    Davis, John N.

    2013-01-01

    Vesicular stomatitis virus (VSV) has shown considerable promise both as an immunization vector and as an oncolytic virus. In both applications, an important concern is the safety profile of the virus. To generate a highly attenuated virus, we added two reporter genes to the 3′ end of the VSV genome, thereby shifting the NPMGL genes from positions 1 to 5 to positions 3 to 7. The resulting virus (VSV-12′GFP) was highly attenuated, generating smaller plaques than four other attenuated VSVs. In one-step growth curves, VSV-12′GFP displayed the slowest growth kinetics. The mechanism of attenuation appears to be due to reduced expression of VSV genes downstream of the reporter genes, as suggested by a 10.4-fold reduction in L-protein RNA transcript. Although attenuated, VSV-12′GFP was highly effective at generating an immune response, indicated by a high-titer antibody response against the green fluorescent protein (GFP) expressed by the virus. Although VSV-12′GFP was more attenuated than other VSVs on both normal and cancer cells, it nonetheless showed a greater level of infection of human cancer cells (glioma and melanoma) than of normal cells, and this effect was magnified in glioma by interferon application, indicating selective oncolysis. Intravenous VSV-12′GFP selectively infected human gliomas implanted into SCID mice subcutaneously or intracranially. All postnatal day 16 mice given intranasal VSV-12′GFP survived, whereas only 10% of those given VSV-G/GFP survived, indicating reduced neurotoxicity. Intratumoral injection of tumors with VSV-12′GFP dramatically suppressed tumor growth and enhanced survival. Together these data suggest this recombinant virus merits further study for its oncolytic and vaccine potential. PMID:23135719

  2. Highly attenuated recombinant vesicular stomatitis virus VSV-12'GFP displays immunogenic and oncolytic activity.

    Science.gov (United States)

    van den Pol, Anthony N; Davis, John N

    2013-01-01

    Vesicular stomatitis virus (VSV) has shown considerable promise both as an immunization vector and as an oncolytic virus. In both applications, an important concern is the safety profile of the virus. To generate a highly attenuated virus, we added two reporter genes to the 3' end of the VSV genome, thereby shifting the NPMGL genes from positions 1 to 5 to positions 3 to 7. The resulting virus (VSV-12'GFP) was highly attenuated, generating smaller plaques than four other attenuated VSVs. In one-step growth curves, VSV-12'GFP displayed the slowest growth kinetics. The mechanism of attenuation appears to be due to reduced expression of VSV genes downstream of the reporter genes, as suggested by a 10.4-fold reduction in L-protein RNA transcript. Although attenuated, VSV-12'GFP was highly effective at generating an immune response, indicated by a high-titer antibody response against the green fluorescent protein (GFP) expressed by the virus. Although VSV-12'GFP was more attenuated than other VSVs on both normal and cancer cells, it nonetheless showed a greater level of infection of human cancer cells (glioma and melanoma) than of normal cells, and this effect was magnified in glioma by interferon application, indicating selective oncolysis. Intravenous VSV-12'GFP selectively infected human gliomas implanted into SCID mice subcutaneously or intracranially. All postnatal day 16 mice given intranasal VSV-12'GFP survived, whereas only 10% of those given VSV-G/GFP survived, indicating reduced neurotoxicity. Intratumoral injection of tumors with VSV-12'GFP dramatically suppressed tumor growth and enhanced survival. Together these data suggest this recombinant virus merits further study for its oncolytic and vaccine potential.

  3. Recombinant immunomodulating lentogenic or mesogenic oncolytic newcastle disease virus for treatment of pancreatic adenocarcinoma

    NARCIS (Netherlands)

    P.R.A. Buijs (Pascal); S. van Nieuwkoop (Stefan); Vaes, V. (Vincent); R.A.M. Fouchier (Ron); C.H.J. van Eijck (Casper); B.G. van den Hoogen (Bernadette)

    2015-01-01

    textabstractOncolytic Newcastle disease virus (NDV) might be a promising new therapeutic agent for the treatment of pancreatic cancer. We evaluated recombinant NDVs (rNDVs) expressing interferon (rNDV-hIFNβ-F0) or an IFN antagonistic protein (rNDV-NS1-F0), as well as rNDV with

  4. Comparative oncology evaluation of intravenous recombinant oncolytic Vesicular Stomatitis Virus therapy in spontaneous canine cancer.

    Science.gov (United States)

    Naik, Shruthi; Galyon, Gina D; Jenks, Nathan J; Steele, Michael B; Miller, Amber C; Allstadt, Sara D; Suksanpaisan, Lukkana; Peng, Kah Whye; Federspiel, Mark J; Russell, Stephen J; LeBlanc, Amy K

    2017-11-20

    Clinical translation of intravenous therapies to treat disseminated or metastatic cancer is imperative. Comparative oncology, the evaluation of novel cancer therapies in animals with spontaneous cancer, can be utilized to inform and accelerate clinical translation. Preclinical murine studies demonstrate that single shot systemic therapy with a VSV-IFNβ-NIS, a novel recombinant oncolytic Vesicular stomatitis virus (VSV), can induce curative remission in tumor bearing mice. Clinical translation of VSV-IFNβ-NIS therapy is dependent on comprehensive assessment of clinical toxicities, virus shedding, pharmacokinetics, and efficacy in clinically relevant models. Dogs spontaneously develop cancer with comparable etiology, clinical progression and response to therapy as human malignancies. A comparative oncology study was carried out to investigate feasibility and tolerability of intravenous oncolytic VSV-IFNβ-NIS therapy in pet dogs with spontaneous cancer. Nine dogs with various malignancies were treated with a single intravenous dose of VSV-IFNβ-NIS. Two dogs with high-grade peripheral T-cell lymphoma had rapid but transient remission of disseminated disease and transient hepatotoxicity that resolved spontaneously. There was no shedding of infectious virus. Correlative pharmacokinetic studies revealed elevated levels of VSV RNA in blood in dogs with measurable disease remission. This is the first evaluation of intravenous oncolytic virus therapy for spontaneous canine cancer, demonstrating that VSV-IFNβ-NIS is well-tolerated and safe in dogs with advanced or metastatic disease. This approach has informed clinical translation, including dose and target indication selection, leading to a clinical investigation of intravenous VSV-IFNβ-NIS therapy, and provided preliminary evidence of clinical efficacy, and potential biomarkers that correlate with therapeutic response. Copyright ©2017, American Association for Cancer Research.

  5. Current good manufacturing practice production of an oncolytic recombinant vesicular stomatitis viral vector for cancer treatment.

    Science.gov (United States)

    Ausubel, L J; Meseck, M; Derecho, I; Lopez, P; Knoblauch, C; McMahon, R; Anderson, J; Dunphy, N; Quezada, V; Khan, R; Huang, P; Dang, W; Luo, M; Hsu, D; Woo, S L C; Couture, L

    2011-04-01

    Vesicular stomatitis virus (VSV) is an oncolytic virus currently being investigated as a promising tool to treat cancer because of its ability to selectively replicate in cancer cells. To enhance the oncolytic property of the nonpathologic laboratory strain of VSV, we generated a recombinant vector [rVSV(MΔ51)-M3] expressing murine gammaherpesvirus M3, a secreted viral chemokine-binding protein that binds to a broad range of mammalian chemokines with high affinity. As previously reported, when rVSV(MΔ51)-M3 was used in an orthotopic model of hepatocellular carcinoma (HCC) in rats, it suppressed inflammatory cell migration to the virus-infected tumor site, which allowed for enhanced intratumoral virus replication leading to increased tumor necrosis and substantially prolonged survival. These encouraging results led to the development of this vector for clinical translation in patients with HCC. However, a scalable current Good Manufacturing Practice (cGMP)-compliant manufacturing process has not been described for this vector. To produce the quantities of high-titer virus required for clinical trials, a process that is amenable to GMP manufacturing and scale-up was developed. We describe here a large-scale (50-liter) vector production process capable of achieving crude titers on the order of 10(9) plaque-forming units (PFU)/ml under cGMP. This process was used to generate a master virus seed stock and a clinical lot of the clinical trial agent under cGMP with an infectious viral titer of approximately 2 × 10(10) PFU/ml (total yield, 1 × 10(13) PFU). The lot has passed all U.S. Food and Drug Administration-mandated release testing and will be used in a phase 1 clinical translational trial in patients with advanced HCC.

  6. Oncolytic Recombinant Vesicular Stomatitis Virus (VSV) Is Nonpathogenic and Nontransmissible in Pigs, a Natural Host of VSV.

    Science.gov (United States)

    Velazquez-Salinas, Lauro; Naik, Shruthi; Pauszek, Steven J; Peng, Kah-Whye; Russell, Stephen J; Rodriguez, Luis L

    2017-06-01

    Vesicular stomatitis virus (VSV) is a negative-stranded RNA virus that naturally causes disease in livestock including horses, cattle and pigs. The two main identified VSV serotypes are New Jersey (VSNJV) and Indiana (VSIV). VSV is a rapidly replicating, potently immunogenic virus that has been engineered to develop novel oncolytic therapies for cancer treatment. Swine are a natural host for VSV and provide a relevant and well-established model, amenable to biological sampling to monitor virus shedding and neutralizing antibodies. Previous reports have documented the pathogenicity and transmissibility of wild-type isolates and recombinant strains of VSIV and VSNJV using the swine model. Oncolytic VSV engineered to express interferon-beta (IFNβ) and the sodium iodide symporter (NIS), VSV-IFNβ-NIS, has been shown to be a potent new therapeutic agent inducing rapid and durable tumor remission following systemic therapy in preclinical mouse models. VSV-IFNβ-NIS is currently undergoing clinical evaluation for the treatment of advanced cancer in human and canine patients. To support clinical studies and comprehensively assess the risk of transmission to susceptible species, we tested the pathogenicity and transmissibility of oncolytic VSV-IFNβ-NIS using the swine model. Following previously established protocols to evaluate VSV pathogenicity, intradermal inoculation with 107 TCID50 VSV-IFNβ-NIS caused no observable symptoms in pigs. There was no detectable shedding of infectious virus in VSV-IFNβ-NIS in biological excreta of inoculated pigs or exposed naive pigs kept in direct contact throughout the experiment. VSV-IFNβ-NIS inoculated pigs became seropositive for VSV antibodies, while contact pigs displayed no symptoms of VSV infection, and importantly did not seroconvert. These data indicate that oncolytic VSV is both nonpathogenic and not transmissible in pigs, a natural host. These findings support further clinical development of oncolytic VSV-IFNβ-NIS as a

  7. Oncolytic gene therapy with recombinant vaccinia strain GLV-2b372 efficiently kills hepatocellular carcinoma.

    Science.gov (United States)

    Ady, Justin W; Johnsen, Clark; Mojica, Kelly; Heffner, Jacqueline; Love, Damon; Pugalenthi, Amudhan; Belin, Laurence J; Chen, Nanhai G; Yu, Yong A; Szalay, Aladar A; Fong, Yuman

    2015-08-01

    Hepatocellular carcinoma (HCC) commonly presents at a late stage when surgery is no longer a curative option. As such, novel therapies for advanced HCC are needed. Oncolytic viruses are a viable option for cancer therapy owing to their ability to specifically infect, replicate within, and kill cancer cells. In this study, we have investigated the ability of GLV-2b372, a novel light-emitting recombinant vaccinia virus derived from a wild-type Lister strain, to kill HCC. Four human HCC cell lines were assayed in vitro for infectivity and cytotoxicity. Viral replication was quantified via standard viral plaque assays. Flank HCC xenografts generated in athymic nude mice were treated with intratumoral GLV-2b372 to assess for tumor growth inhibition and viral biodistribution. Infectivity occurred in a time- and concentration-dependent manner with 70% cell death in all cell lines by day 5. All cell lines supported efficient viral replication. At 25 days after infection, flank tumor volumes decreased by 50% whereas controls increased by 400%. Tumor tissue demonstrated substantial GLV-2b372 infection at 24 hours, 48 hours, and 2 weeks. We demonstrate that GLV-2b372 efficiently kills human HCC in vitro and in vivo and is a viable treatment option for patients with HCC. Copyright © 2015 Elsevier Inc. All rights reserved.

  8. Cytokine-modified VSV is attenuated for neural pathology, but is both highly immunogenic and oncolytic.

    Science.gov (United States)

    Miller, James; Bidula, Sarah M; Jensen, Troels M; Reiss, Carol Shoshkes

    2009-12-01

    Vesicular stomatitis virus (VSV), an enveloped, nonsegmented, negative-stranded RNA virus, is being tested by several laboratories as an antitumor agent. Unfortunately, viral infection of the central nervous system (CNS) has been observed by many groups following administration to tumor-bearing animals. In rodents, VSV encephalitis is characterized by weight-loss, paralysis, and high mortality. In order to provide protection from VSV infection of the CNS after therapeutic administration, we have attenuated VSV by the introduction of the gene encoding the proinflammatory cytokine interleukin (IL)-23, and designated the new virus VSV23. We hypothesize that while VSV23 is replicating within tumors, resulting in tumor destruction, the expression of IL-23 will enhance host antitumor and antiviral immune responses. In the event that the virus escapes from the tumor, the host's immune system will be activated and the virus will be rapidly cleared from healthy tissue. Experimental VSV23 infection of the CNS is characterized by decreased viral replication, morbidity, and mortality. VSV23 is capable of stimulating the enhanced production of nitric oxide in the CNS, which is critical for elimination of VSV from infected neurons. Intraperitoneal administration of VSV23 stimulates both nonspecific natural killer cell, virus-specific cytolytic T lymphocyte and memory virus-specific proliferative T cell responses against wild-type VSV in splenocytes. Furthermore, VSV23 is able to replicate in, and induce apoptosis of tumor cells in vitro. These data indicate that VSV23 is immunogenic, attenuated and suitable for testing as an efficacious and safe oncolytic agent.

  9. Oncolytic efficacy of recombinant vesicular stomatitis virus and myxoma virus in experimental models of rhabdoid tumors.

    Science.gov (United States)

    Wu, Yushui; Lun, Xueqing; Zhou, Hongyuan; Wang, Limei; Sun, Beichen; Bell, John C; Barrett, John W; McFadden, Grant; Biegel, Jaclyn A; Senger, Donna L; Forsyth, Peter A

    2008-02-15

    Rhabdoid tumors are highly aggressive pediatric tumors that are usually refractory to available treatments. The purpose of this study was to evaluate the therapeutic potential of two oncolytic viruses, myxoma virus (MV) and an attenuated vesicular stomatitis virus (VSV(DeltaM51)), in experimental models of human rhabdoid tumor. Four human rhabdoid tumor cell lines were cultured in vitro and treated with live or inactivated control virus. Cytopathic effect, viral gene expression, infectious viral titers, and cell viability were examined at various time points after infection. To study viral oncolysis in vivo, human rhabdoid tumor cells were implanted s.c. in the hind flank or intracranially in CD-1 nude mice and treated with intratumoral (i.t.) or i.v. injections of live or UV-inactivated virus. Viral distribution and effects on tumor size and survival were assessed. All rhabdoid tumor cell lines tested in vitro were susceptible to productive lethal infections by MV and VSV(DeltaM51). I.t. injection of live MV or VSV(DeltaM51) dramatically reduced the size of s.c. rhabdoid tumor xenografts compared with control animals. I.v. administration of VSV(DeltaM51) or i.t. injection of MV prolonged the median survival of mice with brain xenografts compared with controls (VSV(DeltaM51): 25 days versus 21 days, log-rank test, P = 0.0036; MV: median survival not reached versus 21 days, log-rank test, P = 0.0007). Most of the MV-treated animals (4 of 6; 66.7%) were alive and apparently "cured" when the experiment was arbitrarily ended (>180 days). These results suggest that VSV(DeltaM51) and MV could be novel effective therapies against human rhabdoid tumor.

  10. Some Attenuated Variants of Vesicular Stomatitis Virus Show Enhanced Oncolytic Activity against Human Glioblastoma Cells relative to Normal Brain Cells▿

    OpenAIRE

    Wollmann, Guido; Rogulin, Vitaliy; Simon, Ian; Rose, John K.; van den Pol, Anthony N.

    2009-01-01

    Vesicular stomatitis virus (VSV) has been shown in laboratory studies to be effective against a variety of tumors, including malignant brain tumors. However, attenuation of VSV may be necessary to balance the potential toxicity toward normal cells, particularly when targeting brain tumors. Here we compared 10 recombinant VSV variants resulting from different attenuation strategies. Attenuations included gene shifting (VSV-p1-GFP/RFP), M protein mutation (VSV-M51), G protein cytoplasmic tail t...

  11. New technologies in using recombinant attenuated Salmonella vaccine vectors.

    Science.gov (United States)

    Curtiss, Roy; Xin, Wei; Li, Yuhua; Kong, Wei; Wanda, Soo-Young; Gunn, Bronwyn; Wang, Shifeng

    2010-01-01

    Recombinant attenuated Salmonella vaccines (RASVs) have been constructed to deliver antigens from other pathogens to induce immunity to those pathogens in vaccinated hosts. The attenuation means should ensure that the vaccine survives following vaccination to colonize lymphoid tissues without causing disease symptoms. This necessitates that attenuation and synthesis of recombinant gene encoded protective antigens do not diminish the ability of orally administered vaccines to survive stresses encountered in the gastrointestinal tract. We have eliminated these problems by using RASVs with regulated delayed expression of attenuation and regulated delayed synthesis of recombinant antigens. These changes result in RASVs that colonize effector lymphoid tissues efficiently to serve as "factories" to synthesize protective antigens that induce higher protective immune responses than achieved when using previously constructed RASVs. We have devised a biological containment system with regulated delayed lysis to preclude RASV persistence in vivo and survival if excreted. Attributes were added to reduce the mild diarrhea sometimes experienced with oral live RASVs and to ensure complete safety in newborns. These collective technologies have been used to develop a novel, low-cost, RASV-synthesizing, multiple-protective Streptococcus pneumoniae antigens that will be safe for newborns/infants and will induce protective immunity to diverse S. pneumoniae serotypes after oral immunization.

  12. Cowpox Virus: A New and Armed Oncolytic Poxvirus

    Directory of Open Access Journals (Sweden)

    Marine Ricordel

    2017-12-01

    Full Text Available Oncolytic virus therapy has recently been recognized as a promising new therapeutic approach for cancer treatment. In this study, we are proposing for the first time to evaluate the in vitro and in vivo oncolytic capacities of the Cowpox virus (CPXV. To improve the tumor selectivity and oncolytic activity, we developed a thymidine kinase (TK-deleted CPXV expressing the suicide gene FCU1, which converts the non-toxic prodrug 5-fluorocytosine (5-FC into cytotoxic 5-fluorouracil (5-FU and 5-fluorouridine-5′-monophosphate (5-FUMP. This TK-deleted virus replicated efficiently in human tumor cell lines; however, it was notably attenuated in normal primary cells, thus displaying a good therapeutic index. Furthermore, this new recombinant poxvirus rendered cells sensitive to 5-FC. In vivo, after systemic injection in mice, the TK-deleted variant caused significantly less mortality than the wild-type strain. A biodistribution study demonstrated high tumor selectivity and low accumulation in normal tissues. In human xenograft models of solid tumors, the recombinant CPXV also displayed high replication, inducing relevant tumor growth inhibition. This anti-tumor effect was improved by 5-FC co-administration. These results demonstrated that CPXV is a promising oncolytic vector capable of expressing functional therapeutic transgenes.

  13. Genetic Modification of Oncolytic Newcastle Disease Virus for Cancer Therapy.

    Science.gov (United States)

    Cheng, Xing; Wang, Weijia; Xu, Qi; Harper, James; Carroll, Danielle; Galinski, Mark S; Suzich, JoAnn; Jin, Hong

    2016-06-01

    Clinical development of a mesogenic strain of Newcastle disease virus (NDV) as an oncolytic agent for cancer therapy has been hampered by its select agent status due to its pathogenicity in avian species. Using reverse genetics, we have generated a lead candidate oncolytic NDV based on the mesogenic NDV-73T strain that is no longer classified as a select agent for clinical development. This recombinant NDV has a modification at the fusion protein (F) cleavage site to reduce the efficiency of F protein cleavage and an insertion of a 198-nucleotide sequence into the HN-L intergenic region, resulting in reduced viral gene expression and replication in avian cells but not in mammalian cells. In mammalian cells, except for viral polymerase (L) gene expression, viral gene expression is not negatively impacted or increased by the HN-L intergenic insertion. Furthermore, the virus can be engineered to express a foreign gene while still retaining the ability to grow to high titers in cell culture. The recombinant NDV selectively replicates in and kills tumor cells and is able to drive potent tumor growth inhibition following intratumoral or intravenous administration in a mouse tumor model. The candidate is well positioned for clinical development as an oncolytic virus. Avian paramyxovirus type 1, NDV, has been an attractive oncolytic agent for cancer virotherapy. However, this virus can cause epidemic disease in poultry, and concerns about the potential environmental and economic impact of an NDV outbreak have precluded its clinical development. Here we describe generation and characterization of a highly potent oncolytic NDV variant that is unlikely to cause Newcastle disease in its avian host, representing an essential step toward moving NDV forward as an oncolytic agent. Several attenuation mechanisms have been genetically engineered into the recombinant NDV that reduce chicken pathogenicity to a level that is acceptable worldwide without impacting viral production in

  14. Oncolytic Poxviruses.

    Science.gov (United States)

    Chan, Winnie M; McFadden, Grant

    2014-09-01

    Current standard treatments of cancer can prolong survival of many cancer patients but usually do not effectively cure the disease. Oncolytic virotherapy is an emerging therapeutic for the treatment of cancer that exploits replication-competent viruses to selectively infect and destroy cancerous cells while sparing normal cells and tissues. Clinical and/or preclinical studies on oncolytic viruses have revealed that the candidate viruses being tested in trials are remarkably safe and offer potential for treating many classes of currently incurable cancers. Among these candidates are vaccinia and myxoma viruses, which belong to the family Poxviridae and possess promising oncolytic features. This article describes poxviruses that are being developed for oncolytic virotherapy and summarizes the outcomes of both clinical and preclinical studies. Additionally, studies demonstrating superior efficacy when poxvirus oncolytic virotherapy is combined with conventional therapies are described.

  15. Oncolytic vaccines.

    Science.gov (United States)

    Elsedawy, Noura B; Russell, Stephen J

    2013-10-01

    Oncolytic viruses are ideal platforms for tumor vaccination because they can mediate the direct in situ killing of tumor cells that release a broad array of tumor antigens and alarmins or danger signals thereby cross-priming antitumor cytotoxic T lymphocytes (CTLs), which mediate the indirect killing of uninfected cells. The balance between the direct and indirect killing phases of oncolytic virotherapy is the key to its success and can be manipulated by incorporating various immunomodulatory genes into the oncolytic virus genome. Recently, the interim analysis of a large multicenter Phase III clinical trial for Talimogene laherparepvec, a granulocyte-macrophage colony stimulating factor-armed oncolytic herpes simplex virus, revealed significant improvement in objective response and durable response rates over control arm and a trend toward improved overall survival. Meanwhile, newer oncolytics are being developed expressing additional immunomodulatory transgenes to further enhance cross-priming and the generation of antitumor CTLs and to block the immunosuppressive actions of the tumor microenvironment. Since oncolytic vaccines can be engineered to kill tumor cells directly, modulate the kinetics of the antitumor immune response and reverse the immunosuppressive actions of the tumor, they are predicted to emerge as the preferred immunotherapeutic anticancer weapons of the future.

  16. Oncolytic virotherapy.

    Science.gov (United States)

    Russell, Stephen J; Peng, Kah-Whye; Bell, John C

    2012-07-10

    Oncolytic virotherapy is an emerging treatment modality that uses replication-competent viruses to destroy cancers. Recent advances include preclinical proof of feasibility for a single-shot virotherapy cure, identification of drugs that accelerate intratumoral virus propagation, strategies to maximize the immunotherapeutic action of oncolytic viruses and clinical confirmation of a critical viremic threshold for vascular delivery and intratumoral virus replication. The primary clinical milestone has been completion of accrual in a phase 3 trial of intratumoral herpes simplex virus therapy using talimogene laherparepvec for metastatic melanoma. Key challenges for the field are to select 'winners' from a burgeoning number of oncolytic platforms and engineered derivatives, to transiently suppress but then unleash the power of the immune system to maximize both virus spread and anticancer immunity, to develop more meaningful preclinical virotherapy models and to manufacture viruses with orders-of-magnitude higher yields than is currently possible.

  17. Designing herpes viruses as oncolytics

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    Peters, Cole; Rabkin, Samuel D

    2015-01-01

    Oncolytic herpes simplex virus (oHSV) was one of the first genetically-engineered oncolytic viruses. Because HSV is a natural human pathogen that can cause serious disease, it is incumbent that it can be genetically-engineered or significantly attenuated for safety. Here, we present a detailed explanation of the functions of HSV-1 genes frequently mutated to endow oncolytic activity. These genes are nonessential for growth in tissue culture cells but are important for growth in postmitotic cells, interfering with intrinsic antiviral and innate immune responses or causing pathology, functions dispensable for replication in cancer cells. Understanding the function of these genes leads to informed creation of new oHSVs with better therapeutic efficacy. Virus infection and replication can also be directed to cancer cells through tumor-selective receptor binding and transcriptional- or post-transcriptional miRNA-targeting, respectively. In addition to the direct effects of oHSV on infected cancer cells and tumors, oHSV can be “armed” with transgenes that are: reporters, to track virus replication and spread; cytotoxic, to kill uninfected tumor cells; immune modulatory, to stimulate antitumor immunity; or tumor microenvironment altering, to enhance virus spread or to inhibit tumor growth. In addition to HSV-1, other alphaherpesviruses are also discussed for their oncolytic activity. PMID:26462293

  18. Regression of Human Prostate Tumors and Metastases in Nude Mice following Treatment with the Recombinant Oncolytic Vaccinia Virus GLV-1h68

    Directory of Open Access Journals (Sweden)

    Ivaylo Gentschev

    2010-01-01

    Full Text Available Virotherapy using oncolytic vaccinia virus strains is one of the most promising new strategies for cancer therapy. In the current study, we analyzed the therapeutic efficacy of the oncolytic vaccinia virus GLV-1h68 against two human prostate cancer cell lines DU-145 and PC-3 in cell culture and in tumor xenograft models. By viral proliferation assays and cell survival tests, we demonstrated that GLV-1h68 was able to infect, replicate in, and lyse these prostate cancer cells in culture. In DU-145 and PC-3 tumor xenograft models, a single intravenous injection with GLV-1h68 resulted in a significant reduction of primary tumor size. In addition, the GLV-1h68-infection led to strong inflammatory and oncolytic effects resulting in drastic reduction of regional lymph nodes with PC-3 metastases. Our data documented that the GLV-1h68 virus has a great potential for treatment of human prostate carcinoma.

  19. Trial watch: Oncolytic viruses for cancer therapy.

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    Vacchelli, Erika; Eggermont, Alexander; Sautès-Fridman, Catherine; Galon, Jérôme; Zitvogel, Laurence; Kroemer, Guido; Galluzzi, Lorenzo

    2013-06-01

    Oncolytic virotherapy is emerging as a promising approach for the treatment of several neoplasms. The term "oncolytic viruses" is generally employed to indicate naturally occurring or genetically engineered attenuated viral particles that cause the demise of malignant cells while sparing their non-transformed counterparts. From a conceptual standpoint, oncolytic viruses differ from so-called "oncotropic viruses" in that only the former are able to kill cancer cells, even though both display a preferential tropism for malignant tissues. Of note, such a specificity can originate at several different steps of the viral cycle, including the entry of virions (transductional specificity) as well as their intracellular survival and replication (post-transcriptional and transcriptional specificity). During the past two decades, a large array of replication-competent and replication-incompetent oncolytic viruses has been developed and engineered to express gene products that would specifically promote the death of infected (cancer) cells. However, contrarily to long-standing beliefs, the antineoplastic activity of oncolytic viruses is not a mere consequence of the cytopathic effect, i.e., the lethal outcome of an intense, productive viral infection, but rather involves the elicitation of an antitumor immune response. In line with this notion, oncolytic viruses genetically modified to drive the local production of immunostimulatory cytokines exert more robust therapeutic effects than their non-engineered counterparts. Moreover, the efficacy of oncolytic virotherapy is significantly improved by some extent of initial immunosuppression (facilitating viral replication and spread) followed by the administration of immunostimulatory molecules (boosting antitumor immune responses). In this Trial Watch, we will discuss the results of recent clinical trials that have evaluated/are evaluating the safety and antineoplastic potential of oncolytic virotherapy.

  20. Oncolytic virus immunotherapy for melanoma.

    Science.gov (United States)

    Dharmadhikari, Neal; Mehnert, Janice M; Kaufman, Howard L

    2015-03-01

    Melanoma is a type of skin cancer arising from melanocytes and is increasing in incidence. Although complete surgical excision of early stage lesions may be curative, metastatic melanoma continues to be a major therapeutic challenge. Advances in understanding the molecular pathways that promote tumorigenesis and the interactions between melanoma cells and the immune system have resulted in the approval of several newly targeted agents and immunotherapy strategies for the treatment of advanced disease. Oncolytic virus immunotherapy is a new approach that uses native or attenuated live viruses to selectively kill melanoma cells and induce systemic tumor-specific immune responses. A variety of viruses are now in clinical development with the attenuated oncolytic herpesvirus encoding granulocyte-macrophage colony stimulating factor, known as talimogene laherparepvec, recently demonstrating an improvement in durable response rate in patients with advanced melanoma compared with granulocyte-macrophage colony stimulating factor alone. A major advantage of talimogene laherparepvec and related agents is the limited toxicity and ability to use each individual tumor as a source of antigen to generate a highly specific antitumor immune response. These agents are easily administered in the out-patient setting and may be a reasonable option for patients with limited metastatic tumor burden, those with a good performance status and without extensive prior treatment, and in those who cannot tolerate more difficult therapeutic regimens. Further investigation into the impact on overall survival as monotherapy and combination of oncolytic virus immunotherapy with other forms of immunotherapy merit high priority for further clinical application of these novel agents for the treatment of melanoma and perhaps other cancers as well.

  1. A Strategy for Cultivation of Retargeted Oncolytic Herpes Simplex Viruses in Non-cancer Cells.

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    Leoni, Valerio; Gatta, Valentina; Casiraghi, Costanza; Nicosia, Alfredo; Petrovic, Biljana; Campadelli-Fiume, Gabriella

    2017-05-15

    The oncolytic herpes simplex virus (HSV) that has been approved for clinical practice and those HSVs in clinical trials are attenuated viruses, often with the neurovirulence gene γ 1 34.5 and additional genes deleted. One strategy to engineer nonattenuated oncolytic HSVs consists of retargeting the viral tropism to a cancer-specific receptor of choice, exemplified by HER2 (human epidermal growth factor receptor 2), which is present in breast, ovary, and other cancers, and in detargeting from the natural receptors. Because the HER2-retargeted HSVs strictly depend on this receptor for infection, the viruses employed in preclinical studies were cultivated in HER2-positive cancer cells. The production of clinical-grade viruses destined for humans should avoid the use of cancer cells. Here, we engineered the R-213 recombinant, by insertion of a 20-amino-acid (aa) short peptide (named GCN4) in the gH of R-LM113; this recombinant was retargeted to HER2 through insertion in gD of a single-chain antibody (scFv) to HER2. Next, we generated a Vero cell line expressing an artificial receptor (GCN4R) whose N terminus consists of an scFv to GCN4 and therefore is capable of interacting with GCN4 present in gH of R-213. R-213 replicated as well as R-LM113 in SK-OV-3 cells, implying that addition of the GCN4 peptide was not detrimental to gH. R-213 grew to relatively high titers in Vero-GCN4R cells, efficiently spread from cell to cell, and killed both Vero-GCN4R and SK-OV-3 cells, as expected for an oncolytic virus. Altogether, Vero-GCN4R cells represent an efficient system for cultivation of retargeted oncolytic HSVs in non-cancer cells. IMPORTANCE There is growing interest in viruses as oncolytic agents, which can be administered in combination with immunotherapeutic compounds, including immune checkpoint inhibitors. The oncolytic HSV approved for clinical practice and those in clinical trials are attenuated viruses. An alternative to attenuation is a cancer specificity

  2. Improvement of oncolytic adenovirus vectors through genetic capsid modifications

    NARCIS (Netherlands)

    Vrij, Jeroen de

    2012-01-01

    Recombinant viral vectors hold great promise in the field of cancer gene therapy. While a plethora of viruses is being evaluated as oncolytic agents, human adenoviruses of serotype 5 (HAdV-5) are among the most popular of viruses to be developed. Although clinical studies have demonstrated safety of

  3. Amalgamating Oncolytic Viruses to Enhance Their Safety, Consolidate Their Killing Mechanisms, and Accelerate Their Spread

    Science.gov (United States)

    Ayala-Breton, Camilo; Suksanpaisan, Lukkana; Mader, Emily K; Russell, Stephen J; Peng, Kah-Whye

    2013-01-01

    Oncolytic viruses are structurally and biologically diverse, spreading through tumors and killing them by various mechanisms and with different kinetics. Here, we created a hybrid vesicular stomatitis/measles virus (VSV/MV) that harnesses the safety of oncolytic MV, the speed of VSV, and the tumor killing mechanisms of both viruses. Oncolytic MV targets CD46 and kills by forcing infected cells to fuse with uninfected neighbors, but propagates slowly. VSV spreads rapidly, directly lysing tumor cells, but is neurotoxic and loses oncolytic potency when neuroattenuated by conventional approaches. The hybrid VSV/MV lacks neurotoxicity, replicates rapidly with VSV kinetics, and selectively targets CD46 on tumor cells. Its in vivo performance in a myeloma xenograft model was substantially superior to either MV or widely used recombinant oncolytic VSV-M51. PMID:23842448

  4. Amalgamating oncolytic viruses to enhance their safety, consolidate their killing mechanisms, and accelerate their spread.

    Science.gov (United States)

    Ayala-Breton, Camilo; Suksanpaisan, Lukkana; Mader, Emily K; Russell, Stephen J; Peng, Kah-Whye

    2013-10-01

    Oncolytic viruses are structurally and biologically diverse, spreading through tumors and killing them by various mechanisms and with different kinetics. Here, we created a hybrid vesicular stomatitis/measles virus (VSV/MV) that harnesses the safety of oncolytic MV, the speed of VSV, and the tumor killing mechanisms of both viruses. Oncolytic MV targets CD46 and kills by forcing infected cells to fuse with uninfected neighbors, but propagates slowly. VSV spreads rapidly, directly lysing tumor cells, but is neurotoxic and loses oncolytic potency when neuroattenuated by conventional approaches. The hybrid VSV/MV lacks neurotoxicity, replicates rapidly with VSV kinetics, and selectively targets CD46 on tumor cells. Its in vivo performance in a myeloma xenograft model was substantially superior to either MV or widely used recombinant oncolytic VSV-M51.

  5. AT-21FINAL RESULTS OF A PHASE 1 TRIAL OF AN ONCOLYTIC POLIO/RHINOVIRUS RECOMBINANT (PVSRIPO) AGAINST RECURRENT GLIOBLASTOMA (GBM)

    OpenAIRE

    Desjardins, Annick; Sampson, John; Peters, Katherine; Vlahovic, Gordana; Threatt, Stevie; Herndon, James; Boulton, Susan; Lally-Goss, Denise; McSherry, Frances; Lipp, Eric; Friedman, Allan; Friedman, Henry; Bigner, Darell; Gromeier, Matthias

    2014-01-01

    BACKGROUND: PVSRIPO is the live attenuated, oral (SABIN) serotype 1 poliovirus vaccine containing a heterologous internal ribosomal entry site stemming from human rhinovirus type 2. PVSRIPO recognizes nectin-like molecule-5, an oncofetal cell adhesion molecule and tumor antigen widely expressed ectopically in malignancy. We report results of a phase 1 trial evaluating PVSRIPO delivered intratumorally by convection-enhanced delivery (CED). METHODS: Eligible patients were adults with recurrent ...

  6. A highly attenuated recombinant human respiratory syncytial virus lacking the G protein induces long-lasting protection in cotton rats.

    Science.gov (United States)

    Widjojoatmodjo, Myra N; Boes, Jolande; van Bers, Marleen; van Remmerden, Yvonne; Roholl, Paul J M; Luytjes, Willem

    2010-06-02

    Respiratory syncytial virus (RSV) is a primary cause of serious lower respiratory tract illness for which there is still no safe and effective vaccine available. Using reverse genetics, recombinant (r)RSV and an rRSV lacking the G gene (DeltaG) were constructed based on a clinical RSV isolate (strain 98-25147-X). Growth of both recombinant viruses was equivalent to that of wild type virus in Vero cells, but was reduced in human epithelial cells like Hep-2. Replication in cotton rat lungs could not be detected for DeltaG, while rRSV was 100-fold attenuated compared to wild type virus. Upon single dose intranasal administration in cotton rats, both recombinant viruses developed high levels of neutralizing antibodies and conferred comparable long-lasting protection against RSV challenge; protection against replication in the lungs lasted at least 147 days and protection against pulmonary inflammation lasted at least 75 days. Collectively, the data indicate that a single dose immunization with the highly attenuated DeltaG as well as the attenuated rRSV conferred long term protection in the cotton rat against subsequent RSV challenge, without inducing vaccine enhanced pathology. Since DeltaG is not likely to revert to a less attenuated phenotype, we plan to evaluate this deletion mutant further and to investigate its potential as a vaccine candidate against RSV infection.

  7. CRISPR-Cas9 as a Powerful Tool for Efficient Creation of Oncolytic Viruses

    Directory of Open Access Journals (Sweden)

    Ming Yuan

    2016-03-01

    Full Text Available The development of oncolytic viruses has led to an emerging new class of cancer therapeutics. Although the safety profile has been encouraging, the transition of oncolytic viruses to the clinical setting has been a slow process due to modifications. Therefore, a new generation of more potent oncolytic viruses needs to be exploited, following our better understanding of the complex interactions between the tumor, its microenvironment, the virus, and the host immune response. The conventional method for creation of tumor-targeted oncolytic viruses is based on homologous recombination. However, the creation of new mutant oncolytic viruses with large genomes remains a challenge due to the multi-step process and low efficiency of homologous recombination. The CRISPR-associated endonuclease Cas9 has hugely advanced the potential to edit the genomes of various organisms due to the ability of Cas9 to target a specific genomic site by a single guide RNA. In this review, we discuss the CRISPR-Cas9 system as an efficient viral editing method for the creation of new oncolytic viruses, as well as its potential future applications in the development of oncolytic viruses. Further, this review discusses the potential of off-target effects as well as CRISPR-Cas9 as a tool for basic research into viral biology.

  8. Fighting Cancer with Viruses: Oncolytic Virus Therapy in China.

    Science.gov (United States)

    Wei, Ding; Xu, Jing; Liu, Xin-Yuan; Chen, Zhi-Nan; Bian, Huijie

    2018-02-01

    As part of oncolytic virotherapy to treat cancer, oncolytic viruses (OVs) can selectively infect tumor cells to promote oncolysis of cancer cells, local immunological reactions, and systemic antitumor immunity with minimal toxicity to normal tissues. The immunostimulatory properties of OVs provide enormous benefits for the treatment of cancer. A variety of OVs, including genetically engineered and natural viruses, have shown promise in preclinical models and clinical studies. In 2005, the China Food and Drug Administration approved its first OV drug, Oncorine (H101), for treatment of advanced head and neck cancer. To explore new treatment strategies, >200 recombinant or natural OVs are undergoing in-depth investigation in China, and >250 oncolytic virotherapy-related reports from the OV community in China have been published in the past 5 years. These studies investigated a variety of exogenous genes and combination therapeutic strategies to enhance the treatment effects of OVs. To date, five clinical trials covering four OV agents (Oncorine, OrienX010, KH901, and H103) are ongoing, and additional OV agents are awaiting approval for clinical trials in China. Overall, this research emphasizes that combination therapy, especially tumor immunotherapy coupled with effective system administration strategies, can promote the development of oncolytic virotherapies. This article focuses on studies that were carried out in China in order to give an overview of the past, present, and future of oncolytic virotherapy in China.

  9. Recombinant human leptin attenuates stress axis activity in common carp (Cyprinus carpio L.).

    Science.gov (United States)

    Gorissen, Marnix; Bernier, Nicholas J; Manuel, Remy; de Gelder, Stefan; Metz, Juriaan R; Huising, Mark O; Flik, Gert

    2012-08-01

    Proper functioning of the endocrine stress axis requires communication between the stress axis and other regulatory mechanisms. We here describe an intimate interplay between the stress axis and recombinant human leptin (rhLeptin) in a teleostean fish, the common carp Cyprinus carpio. Restraint stress (by netting up to 96h) increased plasma cortisol but did not affect hepatic leptin expression. Perifusion of pituitary glands or head kidneys with rhLeptin revealed direct effects of rhLeptin on both tissues. RhLeptin suppresses basal and CRF-induced ACTH-secretion in a rapid and concentration-dependent manner. The rhLeptin effect persisted for over an hour after administration had been terminated. RhLeptin decreases basal interrenal cortisol secretion in vitro, and by doing so attenuates ACTH-stimulated cortisol production; rhLeptin does not affect interrenal ACTH-sensitivity. Our findings show that the endocrine stress axis activity and leptin are inseparably linked in a teleostean fish, a notion relevant to further our insights in the evolution of leptin physiology in vertebrates. Copyright © 2012 Elsevier Inc. All rights reserved.

  10. Recombinant human soluble thrombomodulin attenuates FK506-induced endothelial dysfunction through prevention of Akt inactivation.

    Science.gov (United States)

    Eguchi, Ryoji; Fujimori, Yoshihiro; Okada, Masaya; Tamaki, Hiroya; Wakabayashi, Ichiro; Ogawa, Hiroyasu

    2014-04-15

    Thrombomodulin (TM), a transmembrane glycoprotein on vascular endothelial cells, is a naturally occurring anticoagulant. Recombinant human soluble TM (rTM), composed of the extracellular domain of TM, also shows anti-coagulant and anti-inflammatory activity, but the effects of rTM on microangiopathy remain unclear. We reported that FK506 induced endothelial dysfunction through inactivation of Akt and extracellular-regulated kinase 1/2 using a three-dimensional culture blood vessel model. In the present study, we examined the effects of rTM on FK506-induced endothelial dysfunction. We found that rTM suppressed FK506-induced endothelial cell death, but not the breakdown of capillary-like tube structures. rTM prevented FK506-induced inactivation of Akt, but not of extracellular-regulated kinase 1/2. Akt inhibition by LY294002 abrogated the preventive effect of rTM on FK506-induced Akt inactivation and the suppressive effect of rTM on FK506-induced cell death. These results suggest that rTM attenuates FK506-induced endothelial dysfunction through prevention of Akt inactivation. Copyright © 2014 Elsevier Inc. All rights reserved.

  11. Dual ligand insertion in gB and in gD of oncolytic HSVs for the retargeting to a producer Vero cell line and to cancer cells.

    Science.gov (United States)

    Petrovic, Biljana; Leoni, Valerio; Gatta, Valentina; Zaghini, Anna; Vannini, Andrea; Campadelli-Fiume, Gabriella

    2017-12-20

    Oncolytic viruses gain cancer specificity in several ways. Like the majority of viruses, they grow better in cancer cells which are defective in mounting the host response to viruses. Often they are attenuated by deletion or mutation of virulence genes which counteract the host response, or are naturally occurring oncolytic mutants. In contrast, retargeted viruses are not attenuated or deleted; their cancer-specificity rests on a modified, specific tropism for cancer receptors. For herpes simplex virus (HSV)-based oncolytics, the detargeting-retargeting strategies employed so far were based on genetic modifications of gD. Recently, we showed that even gH or gB can serve as retargeting tools. To enable the growth of retargeted HSVs in cells that can be used for clinical grade virus production, a double retargeting strategy has been developed. Here we show that several sites in the N-terminus of gB are suitable to harbour the 20 aa long GCN4 peptide, which readdresses HSV tropism to Vero cells expressing the artificial GCN4 receptor, and thus enables virus cultivation in the producer non-cancer Vero-GCN4R cell line. The gB modifications can be combined with a minimal detargeting modification in gD, consisting in the deletion of two residues, aa 30 and 38, and replacement of aa 38 with the scFv to HER2, for retargeting to the cancer receptor. The panel of recombinants was analysed comparatively in terms of virus growth, cell-to-cell spread, cytotoxicity, in vivo anti-tumor efficacy to define the best double retargeting strategy. IMPORTANCE There is increasing interest in oncolytic viruses, following FDA and EMA approval of HSV Oncovex GM-CSF , and, mainly, because they greatly boost the immune response to the tumor and can be combined with immunotherapeutic agents, particularly checkpoint inhibitors. A strategy to gain cancer specificity and avoid virus attenuation is to retarget the virus tropism to cancer-specific receptors of choice. Cultivation of fully retargeted

  12. Evaluation of Recombinant Attenuated Salmonella Vaccine Strains for Broad Protection against Extraintestinal Pathogenic Escherichia coli

    Directory of Open Access Journals (Sweden)

    Jacob T. Maddux

    2017-10-01

    Full Text Available Antibiotic-resistant bacterial infections are difficult to treat, producing a burden on healthcare and the economy. Extraintestinal pathogenic Escherichia coli (ExPEC strains frequently carry antibiotic resistance genes, cause infections outside of the intestine, and are causative agents of hospital-acquired infections. Developing a prevention strategy against this pathogen is challenging due to its antibiotic resistance and antigenic diversity. E. coli common pilus (ECP is frequently found in ExPEC strains and may serve as a common antigen to induce protection against several ExPEC serotypes. In addition, live recombinant attenuated Salmonella vaccine (RASV strains have been used to prevent Salmonella infection and can also be modified to deliver foreign antigens. Thus, the objective of this study was to design a RASV to produce ECP on its surface and assess its ability to provide protection against ExPEC infections. To constitutively display ECP in a RASV strain, we genetically engineered a vector (pYA4428 containing aspartate-β-semialdehyde dehydrogenase and E. coli ecp genes and introduced it into RASV χ9558. RASV χ9558 containing an empty vector (pYA3337 was used as a control to assess protection conferred by the RASV strain without ECP. We assessed vaccine efficacy in in vitro bacterial inhibition assays and mouse models of ExPEC-associated human infections. We found that RASV χ9558(pYA4428 synthesized the major pilin (EcpA and tip pilus adhesin (EcpD on the bacterial surface. Mice orally vaccinated with RASV χ9558(pYA3337 without ECP or χ9558(pYA4428 with ECP, produced anti-Salmonella LPS and anti-E. coli EcpA and EcpD IgG and IgA antibodies. RASV strains showed protective potential against some E. coli and Salmonella strains as assessed using in vitro assays. In mouse sepsis and urinary tract infection challenge models, both vaccines had significant protection in some internal organs. Overall, this work showed that RASVs can elicit

  13. Retargeting Oncolytic Vesicular Stomatitis Virus to Human T-Cell Lymphotropic Virus Type 1-Associated Adult T-Cell Leukemia

    Science.gov (United States)

    Betancourt, Dillon; Ramos, Juan Carlos

    2015-01-01

    ABSTRACT Adult T cell leukemia/lymphoma (ATL) is an aggressive cancer of CD4/CD25+ T lymphocytes, the etiological agent of which is human T-cell lymphotropic virus type 1 (HTLV-1). ATL is highly refractory to current therapies, making the development of new treatments a high priority. Oncolytic viruses such as vesicular stomatitis virus (VSV) are being considered as anticancer agents since they readily infect transformed cells compared to normal cells, the former appearing to exhibit defective innate immune responses. Here, we have evaluated the efficacy and safety of a recombinant VSV that has been retargeted to specifically infect and replicate in transformed CD4+ cells. This was achieved by replacing the single VSV glycoprotein (G) with human immunodeficiency virus type 1 (HIV-1) gp160 to create a hybrid fusion protein, gp160G. The resultant virus, VSV-gp160G, was found to only target cells expressing CD4 and retained robust oncolytic activity against HTLV-1 actuated ATL cells. VSV-gp160G was further noted to be highly attenuated and did not replicate efficiently in or induce significant cell death of primary CD4+ T cells. Accordingly, VSV-gp160G did not elicit any evidence of neurotoxicity even in severely immunocompromised animals such as NOD/Shi-scid, IL-2Rγ-c-null (NSG) mice. Importantly, VSV-gp160G effectively exerted potent oncolytic activity in patient-derived ATL transplanted into NSG mice and facilitated a significant survival benefit. Our data indicate that VSV-gp160G exerts potent oncolytic efficacy against CD4+ malignant cells and either alone or in conjunction with established therapies may provide an effective treatment in patients displaying ATL. IMPORTANCE Adult T cell leukemia (ATL) is a serious form of cancer with a high mortality rate. HTLV-1 infection is the etiological agent of ATL and, unfortunately, most patients succumb to the disease within a few years. Current treatment options have failed to significantly improve survival rate. In

  14. Retargeting Oncolytic Vesicular Stomatitis Virus to Human T-Cell Lymphotropic Virus Type 1-Associated Adult T-Cell Leukemia.

    Science.gov (United States)

    Betancourt, Dillon; Ramos, Juan Carlos; Barber, Glen N

    2015-12-01

    Adult T cell leukemia/lymphoma (ATL) is an aggressive cancer of CD4/CD25(+) T lymphocytes, the etiological agent of which is human T-cell lymphotropic virus type 1 (HTLV-1). ATL is highly refractory to current therapies, making the development of new treatments a high priority. Oncolytic viruses such as vesicular stomatitis virus (VSV) are being considered as anticancer agents since they readily infect transformed cells compared to normal cells, the former appearing to exhibit defective innate immune responses. Here, we have evaluated the efficacy and safety of a recombinant VSV that has been retargeted to specifically infect and replicate in transformed CD4(+) cells. This was achieved by replacing the single VSV glycoprotein (G) with human immunodeficiency virus type 1 (HIV-1) gp160 to create a hybrid fusion protein, gp160G. The resultant virus, VSV-gp160G, was found to only target cells expressing CD4 and retained robust oncolytic activity against HTLV-1 actuated ATL cells. VSV-gp160G was further noted to be highly attenuated and did not replicate efficiently in or induce significant cell death of primary CD4(+) T cells. Accordingly, VSV-gp160G did not elicit any evidence of neurotoxicity even in severely immunocompromised animals such as NOD/Shi-scid, IL-2Rγ-c-null (NSG) mice. Importantly, VSV-gp160G effectively exerted potent oncolytic activity in patient-derived ATL transplanted into NSG mice and facilitated a significant survival benefit. Our data indicate that VSV-gp160G exerts potent oncolytic efficacy against CD4(+) malignant cells and either alone or in conjunction with established therapies may provide an effective treatment in patients displaying ATL. Adult T cell leukemia (ATL) is a serious form of cancer with a high mortality rate. HTLV-1 infection is the etiological agent of ATL and, unfortunately, most patients succumb to the disease within a few years. Current treatment options have failed to significantly improve survival rate. In this study, we

  15. Novel oncolytic viral therapies in patients with thoracic malignancies

    Directory of Open Access Journals (Sweden)

    Ahmad Z

    2016-12-01

    Full Text Available Zeeshan Ahmad, Robert A Kratzke Department of Medicine, Division of Hematology, Oncology, and Transplantation, University of Minnesota Medical School, Minneapolis, MN, USA Abstract: Oncolytic virotherapy is the use of replication-competent viruses to treat malignancies. The potential of oncolytic virotherapy as an approach to cancer therapy is based on historical evidence that certain viral infections can cause spontaneous remission of both hematologic and solid tumor malignancies. Oncolytic virotherapy may eliminate cancer cells through either direct oncolysis of infected tumor cells or indirect immune-mediated oncolysis of uninfected tumor cells. Recent advances in oncolytic virotherapy include the development of a wide variety of genetically attenuated RNA viruses with precise cellular tropism and the identification of cell-surface receptors that facilitate viral transfer to the tissue of interest. Current research is also focused on targeting metastatic disease by sustaining the release of progeny viruses from infected tumor cells and understanding indirect tumor cell killing through immune-mediated mechanisms of virotherapy. The purpose of this review is to critically evaluate recent evidence on the clinical development of tissue-specific viruses capable of targeting tumor cells and eliciting secondary immune responses in lung cancers and mesothelioma. Keywords: lung cancer, mesothelioma, VSV, adenovirus, measles

  16. Oncolytic viruses as anticancer vaccines

    Directory of Open Access Journals (Sweden)

    Norman eWoller

    2014-07-01

    Full Text Available Oncolytic virotherapy has shown impressive results in preclinical studies and first promising therapeutic outcomes in clinical trials as well. Since viruses are known for a long time as excellent vaccination agents, oncolytic viruses are now designed as novel anticancer agents combining the aspect of lysis-dependent cytoreductive activity with concomitant induction of antitumoral immune responses. Antitumoral immune activation by oncolytic virus infection of tumor tissue comprises both, immediate effects of innate immunity and also adaptive responses for long lasting antitumoral activity which is regarded as the most prominent challenge in clinical oncology. To date, the complex effects of a viral tumor infection on the tumor microenvironment and the consequences for the tumor-infiltrating immune cell compartment are poorly understood. However, there is more and more evidence that a tumor infection by an oncolytic virus opens up a number of options for further immunomodulating interventions such as systemic chemotherapy, generic immunostimulating strategies, dendritic cell-based vaccines, and antigenic libraries to further support clinical efficacy of oncolytic virotherapy.

  17. Oncolytic vaccinia therapy of squamous cell carcinoma

    Directory of Open Access Journals (Sweden)

    Yu Yong A

    2009-07-01

    Full Text Available Abstract Background Novel therapies are necessary to improve outcomes for patients with squamous cell carcinomas (SCC of the head and neck. Historically, vaccinia virus was administered widely to humans as a vaccine and led to the eradication of smallpox. We examined the therapeutic effects of an attenuated, replication-competent vaccinia virus (GLV-1h68 as an oncolytic agent against a panel of six human head and neck SCC cell lines. Results All six cell lines supported viral transgene expression (β-galactosidase, green fluorescent protein, and luciferase as early as 6 hours after viral exposure. Efficient transgene expression and viral replication (>150-fold titer increase over 72 hrs were observed in four of the cell lines. At a multiplicity of infection (MOI of 1, GLV-1h68 was highly cytotoxic to the four cell lines, resulting in ≥ 90% cytotoxicity over 6 days, and the remaining two cell lines exhibited >45% cytotoxicity. Even at a very low MOI of 0.01, three cell lines still demonstrated >60% cell death over 6 days. A single injection of GLV-1h68 (5 × 106 pfu intratumorally into MSKQLL2 xenografts in mice exhibited localized intratumoral luciferase activity peaking at days 2–4, with gradual resolution over 10 days and no evidence of spread to normal organs. Treated animals exhibited near-complete tumor regression over a 24-day period without any observed toxicity, while control animals demonstrated rapid tumor progression. Conclusion These results demonstrate significant oncolytic efficacy by an attenuated vaccinia virus for infecting and lysing head and neck SCC both in vitro and in vivo, and support its continued investigation in future clinical trials.

  18. Oncolytic viruses in cancer therapy.

    Science.gov (United States)

    Vähä-Koskela, Markus J V; Heikkilä, Jari E; Hinkkanen, Ari E

    2007-09-08

    Oncolytic virotherapy is a promising form of gene therapy for cancer, employing nature's own agents to find and destroy malignant cells. The purpose of this review is to provide an introduction to this very topical field of research and to point out some of the current observations, insights and ideas circulating in the literature. We have strived to acknowledge as many different oncolytic viruses as possible to give a broader picture of targeting cancer using viruses. Some of the newest additions to the panel of oncolytic viruses include the avian adenovirus, foamy virus, myxoma virus, yaba-like disease virus, echovirus type 1, bovine herpesvirus 4, Saimiri virus, feline panleukopenia virus, Sendai virus and the non-human coronaviruses. Although promising, virotherapy still faces many obstacles that need to be addressed, including the emergence of virus-resistant tumor cells.

  19. Multiple antigens of Yersinia pestis delivered by live recombinant attenuated Salmonella vaccine strains elicit protective immunity against plague.

    Science.gov (United States)

    Sanapala, Shilpa; Rahav, Hannah; Patel, Hetal; Sun, Wei; Curtiss, Roy

    2016-05-05

    Based on our improved novel Salmonella vaccine delivery platform, we optimized the recombinant attenuated Salmonella typhimurium vaccine (RASV) χ12094 to deliver multiple Yersinia pestis antigens. These included LcrV196 (amino acids, 131-326), Psn encoded on pYA5383 and F1 encoded in the chromosome, their synthesis did not cause adverse effects on bacterial growth. Oral immunization with χ12094(pYA5383) simultaneously stimulated high antibody titers to LcrV, Psn and F1 in mice and presented complete protection against both subcutaneous (s.c.) and intranasal (i.n.) challenges with high lethal doses of Y. pestis CO92. Moreover, no deaths or other disease symptoms were observed in SCID mice orally immunized with χ12094(pYA5383) over a 60-day period. Therefore, the trivalent S. typhimurium-based live vaccine shows promise for a next-generation plague vaccine. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. Recombinant Probiotic Expressing Listeria Adhesion Protein Attenuates Listeria monocytogenes Virulence In Vitro

    Science.gov (United States)

    Koo, Ok Kyung; Amalaradjou, Mary Anne Roshni; Bhunia, Arun K.

    2012-01-01

    Background Listeria monocytogenes, an intracellular foodborne pathogen, infects immunocompromised hosts. The primary route of transmission is through contaminated food. In the gastrointestinal tract, it traverses the epithelial barrier through intracellular or paracellular routes. Strategies to prevent L. monocytogenes entry can potentially minimize infection in high-risk populations. Listeria adhesion protein (LAP) aids L. monocytogenes in crossing epithelial barriers via the paracellular route. The use of recombinant probiotic bacteria expressing LAP would aid targeted clearance of Listeria from the gut and protect high-risk populations from infection. Methodology/Principal Findings The objective was to investigate the ability of probiotic bacteria or LAP-expressing recombinant probiotic Lactobacillus paracasei (LbpLAP) to prevent L. monocytogenes adhesion, invasion, and transwell-based transepithelial translocation in a Caco-2 cell culture model. Several wild type probiotic bacteria showed strong adhesion to Caco-2 cells but none effectively prevented L. monocytogenes infection. Pre-exposure to LbpLAP for 1, 4, 15, or 24 h significantly (Pmonocytogenes in Caco-2 cells, whereas pre-exposure to parental Lb. paracasei had no significant effect. Similarly, LbpLAP pre-exposure reduced L. monocytogenes translocation by as much as 46% after 24 h. LbpLAP also prevented L. monocytogenes-mediated cell damage and compromise of tight junction integrity. Furthermore, LbpLAP cells reduced L. monocytogenes-mediated cell cytotoxicity by 99.8% after 1 h and 79% after 24 h. Conclusions/Significance Wild type probiotic bacteria were unable to prevent L. monocytogenes infection in vitro. In contrast, LbpLAP blocked adhesion, invasion, and translocation of L. monocytogenes by interacting with host cell receptor Hsp60, thereby protecting cells from infection. These data show promise for the use of recombinant probiotics in preventing L. monocytogenes infection in high

  1. A recombinant cystatin from Ascaris lumbricoides attenuates inflammation of DSS-induced colitis.

    Science.gov (United States)

    Coronado, S; Barrios, L; Zakzuk, J; Regino, R; Ahumada, V; Franco, L; Ocampo, Y; Caraballo, L

    2017-04-01

    Helminthiasis may ameliorate inflammatory diseases, such as inflammatory bowel disease and asthma. Information about immunomodulators from Ascaris lumbricoides is scarce, but could be important considering the co-evolutionary relationships between helminths and humans. We evaluated the immunomodulatory effects of a recombinant cystatin from A. lumbricoides on an acute model of dextran sodium sulphate (DSS)-induced colitis in mice. From an A. lumbricoides cDNA library, we obtained a recombinant cystatin (rAl-CPI). Protease activity inhibition was demonstrated on cathepsin B and papain. Immunomodulatory effects were evaluated at two intraperitoneal doses (0.5 and 0.25 μg/G) on mice with DSS-induced colitis. Body weight, colon length, Disease Activity Index (DAI), histological inflammation score, myeloperoxidase (MPO) activity, gene expression of cytokines and cytokines levels in colon tissue were analysed. Treatment with rAl-CPI significantly reduced DAI, MPO activity and inflammation score without toxic effects. Also, IL-10 and TGF-B gene overexpression was observed in rAl-CPI-treated group compared to DSS-exposed control and healthy mice. Furthermore, a reduction in IL-6 and TNF-A expression was found, and this was confirmed by the levels of these cytokines in colonic tissue. In conclusion, rAl-CPI reduces inflammation in a mouse model of DSS-induced colitis, probably by increasing the expression of anti-inflammatory cytokines and reducing pro-inflammatory ones. © 2017 John Wiley & Sons Ltd.

  2. Oncolytic virotherapy including Rigvir and standard therapies in malignant melanoma.

    Science.gov (United States)

    Babiker, Hani M; Riaz, Irbaz Bin; Husnain, Muhammad; Borad, Mitesh J

    2017-01-01

    The treatment of metastatic melanoma has evolved from an era where interferon and chemotherapy were the mainstay of treatments to an era where immunotherapy has become the frontline. Ipilimumab (IgG1 CTLA-4 inhibitor), nivolumab (IgG4 PD-1 inhibitor), pembrolizumab (IgG4 PD-1 inhibitor) and nivolumab combined with ipilimumab have become first-line therapies in patients with metastatic melanoma. In addition, the high prevalence of BRAF mutations in melanoma has led to the discovery and approval of targeted molecules, such as vemurafenib (BRAF kinase inhibitor) and trametinib (MEK inhibitor), as they yielded improved responses and survival in malignant melanoma patients. This is certainly a burgeoning time in immunotherapy drug development, and the aforementioned efforts along with the recent US Food and Drug Administration approval of talimogene laherparepvec (T-VEC), a recombinant oncolytic herpes virus, have paved the way to exploring the role of additional oncolytic viruses, such as the echovirus Rigvir, as new and innovative treatment modalities in patients with melanoma. Herein, we discuss the current standard of care treatment in melanoma with an emphasis on immunotherapy and oncolytic viruses in development.

  3. Human recombinant factor VIIa may improve heat intolerance in mice by attenuating hypothalamic neuronal apoptosis and damage.

    Science.gov (United States)

    Hsu, Chuan-Chih; Chen, Sheng-Hsien; Lin, Cheng-Hsien; Yung, Ming-Chi

    2014-10-01

    Intolerance to heat exposure is believed to be associated with hypothalamo-pituitary-adrenocortical (HPA) axis impairment [reflected by decreases in blood concentrations of both adrenocorticotrophic-hormone (ACTH) and corticosterone]. The purpose of this study was to determine the effect of human recombinant factor VIIa (rfVIIa) on heat intolerance, HPA axis impairment, and hypothalamic inflammation, ischemic and oxidative damage, and apoptosis in mice under heat stress. Immediately after heat stress (41.2 °C for 1 h), mice were treated with vehicle (1 mL/kg of body weight) or rfVIIa (65-270 µg/kg of body weight) and then returned to room temperature (26 °C). Mice still alive on day 4 of heat exposure were considered survivors. Cellular ischemia markers (e.g., glutamate, lactate-to-pyruvate ratio), oxidative damage markers (e.g., nitric oxide metabolite, hydroxyl radials), and pro-inflammatory cytokines (e.g., interleukin-6, interleukin-1β, tumor necrosis factor-α) in hypothalamus were determined. In addition, blood concentrations of both ACTH and corticosterone were measured. Hypothalamic cell damage was assessed by determing the neuronal damage scores, whereas the hypothalamic cell apoptosis was determined by assessing the numbers of cells stained with terminal deoxynucleotidyl transferase-mediated αUTP nick-end labeling, caspase-3-positive cells, and platelet endothelial cell adhesion molecula-1-positive cells in hypothalamus. Compared with vehicle-treated heated mice, rfVIIa-treated heated mice had significantly higher fractional survival (8/10 vs 1/10), lesser thermoregulatory deficit (34.1 vs 24.8 °C), lesser extents of ischemic, oxidative, and inflammatory markers in hypothalamus, lesser neuronal damage scores and apoptosis in hypothalamus, and lesser HPA axis impairment. Human recombinant factor VIIa appears to exert a protective effect against heatstroke by attenuating hypothalamic cell apoptosis (due to ischemic, inflammatory, and oxidative damage

  4. Combining oncolytic virotherapy with p53 tumor suppressor gene therapy

    OpenAIRE

    Bressy, Christian; Hastie, Eric; Grdzelishvili, Valery Z.

    2017-01-01

    Oncolytic virus (OV) therapy utilizes replication-competent viruses to kill cancer cells, leaving non-malignant cells unharmed. With the first U.S. Food and Drug Administration-approved OV, dozens of clinical trials ongoing, and an abundance of translational research in the field, OV therapy is poised to be one of the leading treatments for cancer. A number of recombinant OVs expressing a transgene for p53 (TP53) or another p53 family member (TP63 or TP73) were engineered with the goal of gen...

  5. Recombinant AAV-PR39-mediated hypoxia-inducible factor 1α gene expression attenuates myocardial infarction.

    Science.gov (United States)

    Sun, Lijun; Hao, Yuewen; Nie, Xiaowei; Xu, Jian; Li, Zhenwu; Zhang, Wei; Liu, Ying; Zhang, Xuexin

    2014-01-01

    PR39 is an angiogenic masterswitch protein, belonging to the second generation of angiogenic growth factors. However, the role of recombinant adeno-associated virus (AAV) carrying the PR39 fusion gene (AAV-PR39) in acute myocardial infarction remains unclear. Therefore, in this study, we investigated the role of AAV-PR39 in an experimental animal model of acute myocardial infarction. The PR39 gene was fused with the transmembrane peptide, TAT, 6xHis‑tag and NT4 signal sequences. AAV-PR39 was then obtained by calcium phosphate co-precipitation. A total of 18 healthy Chinese mini pigs were randomly divided into an experimental groups (the AAV-PR39-treated group) and a control group [phosphated-buffered saline (PBS)-treated group]. Following the induction of myocardial infarction, enhanced 3.0T MR imaging was performed to observe the changes in myocardial signal intensity at 0 h, 1, 2 and 3 weeks. The expression of hypoxia-inducible factor‑1α (HIF-1α) in the myocardial tissues was determined by SABC immunohistochemistry. In addition, in vitro experiments using CRL-1730 endothelial cells transfected with AAV vector containing NT4-TAT-His-PR39 revealed that the AAV-PR39-treated group had a significantly higher expression of HIF-1α compared with the control group. Moreover, PR39 regulated the HIF-1α-induced expression of angiogenic growth factors. Under hypoxic conditions, the anti-apoptotic effects in the AAV-PR39 group were more pronounced than those observed in the control (PBS-treated) group. In vivo, the enforced expression of recombinant PR39 elevated the level of HIF-1α under hypoxic conditions and decreased the size of the infarcted areas by upregulating the expression of HIF-1α in the areas surrounding the infarct area. Taken together, our data demonstrate that the recombinant AAV-PR39-mediated HIF-1α expression attenuates myocardial infarction, indicating that AAV-PR39 may serve as a novel therapeutic agent for the treatment of myocardial infarction.

  6. Type III interferon attenuates a vesicular stomatitis virus-based vaccine vector.

    Science.gov (United States)

    Guayasamin, Ryann C; Reynolds, Tracy D; Wei, Xin; Fujiwara, Mai; Robek, Michael D

    2014-09-01

    Vesicular stomatitis virus (VSV) has been extensively studied as a vaccine vector and oncolytic agent. Nevertheless, safety concerns have limited its widespread use in humans. The type III lambda interferon (IFN-λ) family of cytokines shares common signaling pathways with the IFN-α/β family and thus evokes similar antiviral activities. However, IFN-λ signals through a distinct receptor complex that is expressed in a cell type-specific manner, which restricts its activity to epithelial barriers, particularly those corresponding to the respiratory and gastrointestinal tracts. In this study, we determined how IFN-λ expression from recombinant VSV would influence vector replication, spread, and immunogenicity. We demonstrate that IFN-λ expression severely attenuates VSV in cell culture. In vivo, IFN-λ limits VSV replication in the mouse lung after intranasal administration and reduces virus spread to other organs. Despite this attenuation, however, the vector retains its capacity to induce protective CD8 T cell and antibody responses after a single immunization. These findings demonstrate a novel method of viral vector attenuation that could be used in both vaccine and oncolytic virus applications. Viruses such as VSV that are used as vaccine vectors can induce protective T cell and antibody responses after a single dose. Additionally, IFN-λ is a potent antiviral agent that has certain advantages for clinical use compared to IFN-α/β, such as fewer patient side effects. Here, we demonstrate that IFN-λ attenuates VSV replication and spread following intranasal virus delivery but does not reduce the ability of VSV to induce potent protective immune responses. These findings demonstrate that the type III IFN family may have widespread applicability for improving the safety and efficacy of viral vaccine and oncolytic vectors. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

  7. Recombinant Adeno-Associated Virus-Mediated Expression of Methamphetamine Antibody Attenuates Methamphetamine-Induced Hyperactivity in Mice.

    Science.gov (United States)

    Chen, Yun-Hsiang; Wu, Kuo-Jen; Wu, Kuang-Lun; Wu, Kun-Lieh; Tsai, Ho-Min; Chen, Mao-Liang; Chen, Yi-Wei; Hsieh, Wei; Lin, Chun-Ming; Wang, Yun

    2017-04-07

    Methamphetamine (Meth) is one of the most frequently abused drugs worldwide. Recent studies have indicated that antibodies with high affinity for Meth reduce its pharmacological effects. The purpose of this study was to develop a technique for virus-based passive immunization against Meth effects. We generated a recombinant adeno-associated virus serotype-8 vector (AAV-MethAb) carrying the gene for a Meth-specific monoclonal antibody (MethAb). Infection of 293 cells with AAV-MethAb resulted in the expression and secretion of antibodies which bind to Meth. The viral vector was then examined in adult ICR mice. Systemic administration of AAV-MethAb resulted in long-term expression of MethAb in the serum for up to 29 weeks. Serum collected from the animals receiving AAV-MethAb retained a high specificity for (+)-Meth. Animals were challenged with Meth five weeks after viral injection. Meth levels in the brain and serum were reduced while Meth-induced locomotor activity was significantly attenuated. In conclusion, AAV-MethAb administration effectively depletes Meth from brain and serum while reducing the behavioral response to Meth, and thus is a potential therapeutic approach for Meth abuse.

  8. Oncolytic virotherapy for ovarian cancer

    Science.gov (United States)

    Li, Shoudong; Tong, Jessica; Rahman, Masmudur M; Shepherd, Trevor G; McFadden, Grant

    2012-01-01

    In the past two decades, more than 20 viruses with selective tropism for tumor cells have been developed as oncolytic viruses (OVs) for treatments of a variety of malignancies. Of these viruses, eleven have been tested in human ovarian cancer models in preclinical studies. So far, nine phase I or II clinical trials have been conducted or initiated using four different types of OVs in patients with recurrent ovarian cancers. In this article, we summarize the different OVs that are being assessed as therapeutics for ovarian cancer. We also present an overview of recent advances in identification of key genetic or immune-response pathways involved in tumorigenesis of ovarian cancer, which provides a better understanding of the tumor specificities and oncolytic properties of OVs. In addition, we discuss how next-generation OVs could be genetically modified or integrated into multimodality regimens to improve clinical outcomes based on recent advances in ovarian cancer biology. PMID:25977900

  9. [Current state of oncolytic virotherapy in Japan].

    Science.gov (United States)

    Nakamori, Mikihito; Yamaue, Hiroki

    2013-05-01

    Oncolytic virotherapy is an emerging treatment strategy that uses replication-competent viruses to destroy cancers. Recent advances include preclinical proof of feasibility for a single-shot virotherapy cure, identification of drugs that accelerate intratumoral virus propagation, and strategies to maximize the immunotherapeutic action of oncolytic viruses. The primary clinical milestone has been completion of accrual in a phase 3 trial of intratumoral herpes simplex virus therapy using OncoVEX for metastatic melanoma. In Japan, clinical treatments such as oncolytic adenoviruses(OBP-301)for esophageal cancer and oncolytic herpes simplex viruses(G47b)for brain cancer have accelerated considerably. We hope that a steady stream of new oncolytic viruses will enter the clinical arena in our country.

  10. Synergistic interaction between oncolytic viruses augments tumor killing.

    Science.gov (United States)

    Le Boeuf, Fabrice; Diallo, Jean-Simon; McCart, J Andrea; Thorne, Steve; Falls, Theresa; Stanford, Marianne; Kanji, Femina; Auer, Rebecca; Brown, Christopher W; Lichty, Brian D; Parato, Kelley; Atkins, Harold; Kirn, David; Bell, John C

    2010-05-01

    A major barrier to all oncolytic viruses (OVs) in clinical development is cellular innate immunity, which is variably active in a spectrum of human malignancies. To overcome the heterogeneity of tumor response, we combined complementary OVs that attack cancers in distinct ways to improve therapeutic outcome. Two genetically distinct viruses, vesicular stomatitis virus (VSV) and vaccinia virus (VV), were used to eliminate the risk of recombination. The combination was tested in a variety of tumor types in vitro, in immunodeficient and immunocompetent mouse tumor models, and ex vivo, in a panel of primary human cancer samples. We found that VV synergistically enhanced VSV antitumor activity, dependent in large part on the activity of the VV B18R gene product. A recombinant version of VSV expressing the fusion-associated small-transmembrane (p14FAST) protein also further enhanced the ability of VV to spread through an infected monolayer, resulting in a "ping pong" oncolytic effect wherein each virus enhanced the ability of the other to replicate and/or spread in tumor cells. Our strategy is the first example where OVs are rationally combined to utilize attributes of different OVs to overcome the heterogeneity of malignancies and demonstrates the feasibility of combining complementary OVs to improve therapeutic outcome.

  11. A Recombinant Respiratory Syncytial Virus Vaccine Candidate Attenuated by a Low-Fusion F Protein Is Immunogenic and Protective against Challenge in Cotton Rats.

    Science.gov (United States)

    Rostad, Christina A; Stobart, Christopher C; Gilbert, Brian E; Pickles, Ray J; Hotard, Anne L; Meng, Jia; Blanco, Jorge C G; Moin, Syed M; Graham, Barney S; Piedra, Pedro A; Moore, Martin L

    2016-08-15

    Although respiratory syncytial virus (RSV) is the leading cause of lower respiratory tract infections in infants, a safe and effective vaccine is not yet available. Live-attenuated vaccines (LAVs) are the most advanced vaccine candidates in RSV-naive infants. However, designing an LAV with appropriate attenuation yet sufficient immunogenicity has proven challenging. In this study, we implemented reverse genetics to address these obstacles with a multifaceted LAV design that combined the codon deoptimization of genes for nonstructural proteins NS1 and NS2 (dNS), deletion of the small hydrophobic protein (ΔSH) gene, and replacement of the wild-type fusion (F) protein gene with a low-fusion RSV subgroup B F consensus sequence of the Buenos Aires clade (BAF). This vaccine candidate, RSV-A2-dNS-ΔSH-BAF (DB1), was attenuated in two models of primary human airway epithelial cells and in the upper and lower airways of cotton rats. DB1 was also highly immunogenic in cotton rats and elicited broadly neutralizing antibodies against a diverse panel of recombinant RSV strains. When vaccinated cotton rats were challenged with wild-type RSV A, DB1 reduced viral titers in the upper and lower airways by 3.8 log10 total PFU and 2.7 log10 PFU/g of tissue, respectively, compared to those in unvaccinated animals (P < 0.0001). DB1 was thus attenuated, highly immunogenic, and protective against RSV challenge in cotton rats. DB1 is the first RSV LAV to incorporate a low-fusion F protein as a strategy to attenuate viral replication and preserve immunogenicity. RSV is a leading cause of infant hospitalizations and deaths. The development of an effective vaccine for this high-risk population is therefore a public health priority. Although live-attenuated vaccines have been safely administered to RSV-naive infants, strategies to balance vaccine attenuation with immunogenicity have been elusive. In this study, we introduced a novel strategy to attenuate a recombinant RSV vaccine by

  12. Trial Watch:: Oncolytic viruses for cancer therapy.

    Science.gov (United States)

    Pol, Jonathan; Bloy, Norma; Obrist, Florine; Eggermont, Alexander; Galon, Jérôme; Cremer, Isabelle; Erbs, Philippe; Limacher, Jean-Marc; Preville, Xavier; Zitvogel, Laurence; Kroemer, Guido; Galluzzi, Lorenzo

    2014-01-01

    Oncolytic viruses are natural or genetically modified viral species that selectively infect and kill neoplastic cells. Such an innate or exogenously conferred specificity has generated considerable interest around the possibility to employ oncolytic viruses as highly targeted agents that would mediate cancer cell-autonomous anticancer effects. Accumulating evidence, however, suggests that the therapeutic potential of oncolytic virotherapy is not a simple consequence of the cytopathic effect, but strongly relies on the induction of an endogenous immune response against transformed cells. In line with this notion, superior anticancer effects are being observed when oncolytic viruses are engineered to express (or co-administered with) immunostimulatory molecules. Although multiple studies have shown that oncolytic viruses are well tolerated by cancer patients, the full-blown therapeutic potential of oncolytic virotherapy, especially when implemented in the absence of immunostimulatory interventions, remains unclear. Here, we cover the latest advances in this active area of translational investigation, summarizing high-impact studies that have been published during the last 12 months and discussing clinical trials that have been initiated in the same period to assess the therapeutic potential of oncolytic virotherapy in oncological indications.

  13. Oncolytic virotherapy including Rigvir and standard therapies in malignant melanoma

    Directory of Open Access Journals (Sweden)

    Babiker HM

    2017-02-01

    Full Text Available Hani M Babiker,1 Irbaz Bin Riaz,2 Muhammad Husnain,2 Mitesh J Borad3,4 1University of Arizona Cancer Center, 2Department of Internal Medicine, University of Arizona, Tucson, 3Division of Hematology-Oncology, Mayo Clinic Cancer Center, Scottsdale, AZ, 4Department of Molecular Medicine, Center for Individualized Medicine, Mayo Clinic, Rochester, MN, USA Abstract: The treatment of metastatic melanoma has evolved from an era where interferon and chemotherapy were the mainstay of treatments to an era where immunotherapy has become the frontline. Ipilimumab (IgG1 CTLA-4 inhibitor, nivolumab (IgG4 PD-1 inhibitor, pembrolizumab (IgG4 PD-1 inhibitor and nivolumab combined with ipilimumab have become first-line therapies in patients with metastatic melanoma. In addition, the high prevalence of BRAF mutations in melanoma has led to the discovery and approval of targeted molecules, such as vemurafenib (BRAF kinase inhibitor and trametinib (MEK inhibitor, as they yielded improved responses and survival in malignant melanoma patients. This is certainly a burgeoning time in immunotherapy drug development, and the aforementioned efforts along with the recent US Food and Drug Administration approval of talimogene laherparepvec (T-VEC, a recombinant oncolytic herpes virus, have paved the way to exploring the role of additional oncolytic viruses, such as the echovirus Rigvir, as new and innovative treatment modalities in patients with melanoma. Herein, we discuss the current standard of care treatment in melanoma with an emphasis on immunotherapy and oncolytic viruses in development. Keywords: melanoma, virotherapy, Rigvir

  14. Safety Overview of a Recombinant Live-Attenuated Tetravalent Dengue Vaccine: Pooled Analysis of Data from 18 Clinical Trials.

    Directory of Open Access Journals (Sweden)

    Sophia Gailhardou

    2016-07-01

    Full Text Available A recombinant live attenuated tetravalent dengue vaccine (CYD-TDV has been shown to be efficacious in preventing virologically-confirmed dengue disease, severe dengue disease and dengue hospitalization in children aged 2-16 years in Asia and Latin America. We analyzed pooled safety data from 18 phase I, II and III clinical trials in which the dengue vaccine was administered to participants aged 2-60 years, including long-term safety follow-up in three efficacy trials. The participants were analyzed according to their age at enrollment. The percentage of participants aged 2-60 years reporting ≥1 solicited injection-site or systemic reactions was slightly higher in the CYD-TDV group than in the placebo group. The most common solicited injection-site reactions were pain. Headache and malaise were the most common solicited systemic reactions. In both groups 0.3% of participants discontinued for safety reasons. The most common unsolicited adverse events were injection-site reactions, gastrointestinal disorders, and infections. Reactogenicity did not increase with successive doses of CYD-TDV. The frequency and nature of SAEs occurring within 28 days of any dose were similar in the CYD-TDV and placebo groups and were common medical conditions that could be expected as a function of age. Baseline dengue virus serostatus did not appear to influence the safety profile. No vaccine-related anaphylactic reactions, neurotropic events or viscerotropic events were reported. In year 3 after dose 1, an imbalance for dengue hospitalization, including for severe dengue, observed in participants aged <9 years in the CYD-TDV group compared with the placebo group was not observed for participants aged ≥9 years. In Year 4, this imbalance in participants aged <9 years was less marked, giving an overall lower risk of dengue hospitalization or severe dengue from dose 1 to Year 4 in the CYD-TDV group. These results have contributed to the definition of the target

  15. Safety Overview of a Recombinant Live-Attenuated Tetravalent Dengue Vaccine: Pooled Analysis of Data from 18 Clinical Trials.

    Science.gov (United States)

    Gailhardou, Sophia; Skipetrova, Anna; Dayan, Gustavo H; Jezorwski, John; Saville, Melanie; Van der Vliet, Diane; Wartel, T Anh

    2016-07-01

    A recombinant live attenuated tetravalent dengue vaccine (CYD-TDV) has been shown to be efficacious in preventing virologically-confirmed dengue disease, severe dengue disease and dengue hospitalization in children aged 2-16 years in Asia and Latin America. We analyzed pooled safety data from 18 phase I, II and III clinical trials in which the dengue vaccine was administered to participants aged 2-60 years, including long-term safety follow-up in three efficacy trials. The participants were analyzed according to their age at enrollment. The percentage of participants aged 2-60 years reporting ≥1 solicited injection-site or systemic reactions was slightly higher in the CYD-TDV group than in the placebo group. The most common solicited injection-site reactions were pain. Headache and malaise were the most common solicited systemic reactions. In both groups 0.3% of participants discontinued for safety reasons. The most common unsolicited adverse events were injection-site reactions, gastrointestinal disorders, and infections. Reactogenicity did not increase with successive doses of CYD-TDV. The frequency and nature of SAEs occurring within 28 days of any dose were similar in the CYD-TDV and placebo groups and were common medical conditions that could be expected as a function of age. Baseline dengue virus serostatus did not appear to influence the safety profile. No vaccine-related anaphylactic reactions, neurotropic events or viscerotropic events were reported. In year 3 after dose 1, an imbalance for dengue hospitalization, including for severe dengue, observed in participants aged dengue hospitalization or severe dengue from dose 1 to Year 4 in the CYD-TDV group. These results have contributed to the definition of the target population for vaccination (≥9 years old) for which CYD-TDV has a satisfactory safety profile. Long-term safety will continue to be monitored in the ongoing follow-up of efficacy trials. Safety and effectiveness in real-life settings will

  16. Oncolytic immunotherapy: unlocking the potential of viruses to help target cancer.

    Science.gov (United States)

    Hamid, Omid; Hoffner, Brianna; Gasal, Eduard; Hong, Jenny; Carvajal, Richard D

    2017-07-15

    Oncolytic immunotherapy is a research area of cancer immunotherapy investigating the use of modified viruses to target cancer cells. A variety of different viral backbones (e.g., adenovirus, reovirus) with a diverse range of genetic modifications are currently being investigated for the treatment of a variety of cancers. The oncolytic virus that has advanced the furthest in clinical development is talimogene laherparepvec, a recombinant HSV-1 virus expressing granulocyte-macrophage colony-stimulating factor (GM-CSF). In a phase 3 study in patients with unresectable metastatic melanoma, intralesional talimogene laherparepvec treatment resulted in a higher durable response rate compared with subcutaneous GM-CSF treatment (16.3 versus 2.1%; P < 0.001). Notably, responses were observed at uninjected lesions including visceral lesions, indicating a systemic antitumor response had occurred. Studies evaluating combination treatments involving oncolytic viruses and immunologic agents are ongoing. This review focuses on the mechanisms of action for oncolytic viruses and highlights select agents and combinations currently in development.

  17. Prospects for combined use of oncolytic viruses and CAR T-cells.

    Science.gov (United States)

    Ajina, Adam; Maher, John

    2017-11-21

    With the approval of talimogene laherparepvec (T-VEC) for inoperable locally advanced or metastatic malignant melanoma in the USA and Europe, oncolytic virotherapy is now emerging as a viable therapeutic option for cancer patients. In parallel, following the favourable results of several clinical trials, adoptive cell transfer using chimeric antigen receptor (CAR)-redirected T-cells is anticipated to enter routine clinical practice for the management of chemotherapy-refractory B-cell malignancies. However, CAR T-cell therapy for patients with advanced solid tumours has proved far less successful. This Review draws upon recent advances in the design of novel oncolytic viruses and CAR T-cells and provides a comprehensive overview of the synergistic potential of combination oncolytic virotherapy with CAR T-cell adoptive cell transfer for the management of solid tumours, drawing particular attention to the methods by which recombinant oncolytic viruses may augment CAR T-cell trafficking into the tumour microenvironment, mitigate or reverse local immunosuppression and enhance CAR T-cell effector function and persistence.

  18. Viral Oncolytic Therapeutics for Neoplastic Meningitis

    Science.gov (United States)

    2014-09-01

    Award Number: W81XWH-11-1-0387 TITLE: Viral Oncolytic Therapeutics for Neoplastic Meningitis PRINCIPAL INVESTIGATOR: Mikhail Papisov, PhD...SUBTITLE Viral Oncolytic Therapeutics for Neoplastic Meningitis 5a. CONTRACT NUMBER 5b. GRANT NUMBER W81XWH-11-1-0387 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR...for neoplastic meningitis ( meningeal metastasis of breast cancer). The proposed therapy will be based on direct (intrathecal) administration of

  19. Oncolytic Myxoma Virus: The path to clinic

    OpenAIRE

    Chan, Winnie M.; Rahman, Masmudur M.; McFadden, Grant

    2013-01-01

    Many common neoplasms are still noncurative with current standards of cancer therapy. More therapeutic modalities need to be developed to significantly prolong the lives of patients and eventually cure a wider spectrum of cancers. Oncolytic virotherapy is one of the promising new additions to clinical cancer therapeutics. Successful oncolytic virotherapy in the clinic will be those strategies that best combine tumor cell oncolysis with enhanced immune responses against tumor antigens. The cur...

  20. Evidence for differential viral oncolytic efficacy in an in vitro model of epithelial ovarian cancer metastasis

    Directory of Open Access Journals (Sweden)

    Jessica G Tong

    2015-01-01

    Full Text Available Epithelial ovarian cancer is unique among most carcinomas in that metastasis occurs by direct dissemination of malignant cells traversing throughout the intraperitoneal fluid. Accordingly, we test new therapeutic strategies using an in vitro three-dimensional spheroid suspension culture model that mimics key steps of this metastatic process. In the present study, we sought to uncover the differential oncolytic efficacy among three different viruses—Myxoma virus, double-deleted vaccinia virus, and Maraba virus—using three ovarian cancer cell lines in our metastasis model system. Herein, we demonstrate that Maraba virus effectively infects, replicates, and kills epithelial ovarian cancer (EOC cells in proliferating adherent cells and with slightly slower kinetics in tumor spheroids. Myxoma virus and vaccinia viruses infect and kill adherent cells to a much lesser extent than Maraba virus, and their oncolytic potential is almost completely attenuated in spheroids. Myxoma virus and vaccinia are able to infect and spread throughout spheroids, but are blocked in the final stages of the lytic cycle, and oncolytic-mediated cell killing is reactivated upon spheroid reattachment. Alternatively, Maraba virus has a remarkably reduced ability to initially enter spheroid cells, yet rapidly infects and spreads throughout spheroids generating significant cell killing effects. We show that low-density lipoprotein receptor expression in ovarian cancer spheroids is reduced and this controls efficient Maraba virus binding and entry into infected cells. Taken together, these results are the first to implicate the potential impact of differential viral oncolytic properties at key steps of ovarian cancer metastasis.

  1. Evidence for differential viral oncolytic efficacy in an in vitro model of epithelial ovarian cancer metastasis.

    Science.gov (United States)

    Tong, Jessica G; Valdes, Yudith Ramos; Barrett, John W; Bell, John C; Stojdl, David; McFadden, Grant; McCart, J Andrea; DiMattia, Gabriel E; Shepherd, Trevor G

    2015-01-01

    Epithelial ovarian cancer is unique among most carcinomas in that metastasis occurs by direct dissemination of malignant cells traversing throughout the intraperitoneal fluid. Accordingly, we test new therapeutic strategies using an in vitro three-dimensional spheroid suspension culture model that mimics key steps of this metastatic process. In the present study, we sought to uncover the differential oncolytic efficacy among three different viruses-Myxoma virus, double-deleted vaccinia virus, and Maraba virus-using three ovarian cancer cell lines in our metastasis model system. Herein, we demonstrate that Maraba virus effectively infects, replicates, and kills epithelial ovarian cancer (EOC) cells in proliferating adherent cells and with slightly slower kinetics in tumor spheroids. Myxoma virus and vaccinia viruses infect and kill adherent cells to a much lesser extent than Maraba virus, and their oncolytic potential is almost completely attenuated in spheroids. Myxoma virus and vaccinia are able to infect and spread throughout spheroids, but are blocked in the final stages of the lytic cycle, and oncolytic-mediated cell killing is reactivated upon spheroid reattachment. Alternatively, Maraba virus has a remarkably reduced ability to initially enter spheroid cells, yet rapidly infects and spreads throughout spheroids generating significant cell killing effects. We show that low-density lipoprotein receptor expression in ovarian cancer spheroids is reduced and this controls efficient Maraba virus binding and entry into infected cells. Taken together, these results are the first to implicate the potential impact of differential viral oncolytic properties at key steps of ovarian cancer metastasis.

  2. Myxoma virus and oncolytic virotherapy: a new biologic weapon in the war against cancer.

    Science.gov (United States)

    Stanford, Marianne M; McFadden, Grant

    2007-09-01

    Oncolytic virotherapy is an innovative alternative to more conventional cancer therapies. The ability of some viruses to specifically target and kill malignant cancerous cells while leaving normal tissue unscathed has opened a large repertoire of new and selective cancer killing therapeutic candidates. Poxviruses, such as vaccinia virus, have a long history of use in humans as live vaccines and have more recently been studied as potential platforms for delivery of immunotherapeutics and attenuated variants of vaccinia have been explored as oncolytic candidates. In contrast, the poxvirus myxoma virus is a novel oncolytic candidate that has no history of use in humans directly, as it has a distinct and absolute host species tropism to lagomorphs (rabbits). Myxoma virus has been recently shown to be able to also selectively infect and kill human tumor cells, a unique tropism that is linked to dysregulated intracellular signalling pathways found in the majority of human cancers. This review outlines the existing knowledge on the tropism of myxoma virus for human cancer cells, as well as preclinical data exhibiting its ability to infect and clear tumors in animal models of cancer. This is an exciting new therapeutic option for treating cancer, and myxoma virus joins a growing group of oncolytic virus candidates that are being developed as a new class of cancer therapies in man.

  3. Selective replication of oncolytic virus M1 results in a bystander killing effect that is potentiated by Smac mimetics.

    Science.gov (United States)

    Cai, Jing; Lin, Yuan; Zhang, Haipeng; Liang, Jiankai; Tan, Yaqian; Cavenee, Webster K; Yan, Guangmei

    2017-06-27

    Oncolytic virotherapy is a treatment modality that uses native or genetically modified viruses that selectively replicate in and kill tumor cells. Viruses represent a type of pathogen-associated molecular pattern and thereby induce the up-regulation of dozens of cytokines via activating the host innate immune system. Second mitochondria-derived activator of caspases (Smac) mimetic compounds (SMCs), which antagonize the function of inhibitor of apoptosis proteins (IAPs) and induce apoptosis, sensitize tumor cells to multiple cytokines. Therefore, we sought to determine whether SMCs sensitize tumor cells to cytokines induced by the oncolytic M1 virus, thus enhancing a bystander killing effect. Here, we report that SMCs potentiate the oncolytic effect of M1 in vitro, in vivo, and ex vivo. This strengthened oncolytic efficacy resulted from the enhanced bystander killing effect caused by the M1 virus via cytokine induction. Through a microarray analysis and subsequent validation using recombinant cytokines, we identified IL-8, IL-1A, and TRAIL as the key cytokines in the bystander killing effect. Furthermore, SMCs increased the replication of M1, and the accumulation of virus protein induced irreversible endoplasmic reticulum stress- and c-Jun N-terminal kinase-mediated apoptosis. Nevertheless, the combined treatment with M1 and SMCs had little effect on normal and human primary cells. Because SMCs selectively and significantly enhance the bystander killing effect and the replication of oncolytic virus M1 specifically in cancer cells, this combined treatment may represent a promising therapeutic strategy.

  4. Targeting an Oncolytic Influenza A Virus to Tumor Tissue by Elastase

    Directory of Open Access Journals (Sweden)

    Irina Kuznetsova

    2017-12-01

    Full Text Available Oncolytic viruses are currently established as a novel type of immunotherapy. The challenge is to safely target oncolytic viruses to tumors. Previously, we have generated influenza A viruses (IAVs containing deletions in the viral interferon antagonist. Those deletions have attenuated the virus in normal tissue but allowed replication in tumor cells. IAV entry is mediated by hemagglutinin (HA, which needs to be activated by a serine protease, for example, through trypsin. To further target the IAV to tumors, we have changed the trypsin cleavage site to an elastase cleavage site. We chose this cleavage site because elastase is expressed in the tumor microenvironment. Moreover, the exchange of the cleavage site previously has been shown to attenuate viral growth in lungs. Newly generated elastase-activated influenza viruses (AE viruses grew to similar titers in tumor cells as the trypsin-activated counterparts (AT viruses. Intratumoral injection of AE viruses into syngeneic B16f1 melanoma-derived tumors in mice reduced tumor growth similar to AT viruses and had a better therapeutic effect in heterologous human PANC-1-derived tumors. Therefore, the introduction of the attenuation marker “elastase cleavage site” in viral HA allows for safe, effective oncolytic virus therapy.

  5. Oncolytic Newcastle Disease Virus as treatment for pancreatic cancer

    NARCIS (Netherlands)

    P.R.A. Buijs (Pascal)

    2015-01-01

    markdownabstractAbstract In this thesis, experiments are presented that were undertaken to develop oncolytic NDV for the treatment of pancreatic adenocarcinoma. Oncolytic viruses (OVs), reported first halfway the previous century, have undergone a tremendous evolution from anecdotal experimental

  6. Critical analysis of an oncolytic herpesvirus encoding granulocyte-macrophage colony stimulating factor for the treatment of malignant melanoma.

    Science.gov (United States)

    Hughes, Tasha; Coffin, Robert S; Lilley, Caroline E; Ponce, Rafael; Kaufman, Howard L

    2014-01-01

    Oncolytic viruses that selectively lyse tumor cells with minimal damage to normal cells are a new area of therapeutic development in oncology. An attenuated herpesvirus encoding the granulocyte-macrophage colony stimulating factor (GM-CSF), known as talimogene laherparepvec (T-VEC), has been identified as an attractive oncolytic virus for cancer therapy based on preclinical tumor studies and results from early-phase clinical trials and a large randomized Phase III study in melanoma. In this review, we discuss the basic biology of T-VEC, describe the role of GM-CSF as an immune adjuvant, summarize the preclinical data, and report the outcomes of published clinical trials using T-VEC. The emerging data suggest that T-VEC is a safe and potentially effective antitumor therapy in malignant melanoma and represents the first oncolytic virus to demonstrate therapeutic activity against human cancer in a randomized, controlled Phase III study.

  7. Systemic treatment of xenografts with vaccinia virus GLV-1h68 reveals the immunologic facet of oncolytic therapy

    Directory of Open Access Journals (Sweden)

    Liu Hui

    2009-07-01

    Full Text Available Abstract Background GLV-1h68 is an attenuated recombinant vaccinia virus (VACV that selectively colonizes established human xenografts inducing their complete regression. Results Here, we explored xenograft/VACV/host interactions in vivo adopting organism-specific expression arrays and tumor cell/VACV in vitro comparing VACV replication patterns. There were no clear-cut differences in vitro among responding and non-responding tumors, however, tumor rejection was associated in vivo with activation of interferon-stimulated genes (ISGs and innate immune host's effector functions (IEFs correlating with VACV colonization of the xenografts. These signatures precisely reproduce those observed in humans during immune-mediated tissue-specific destruction (TSD that causes tumor or allograft rejection, autoimmunity or clearance of pathogens. We recently defined these common pathways in the "immunologic constant of rejection" hypothesis (ICR. Conclusion This study provides the first prospective validation of a universal mechanism associated with TSD. Thus, xenograft infection by oncolytic VACV, beyond offering a promising therapy of established cancers, may represent a reliable pre-clinical model to test therapeutic strategies aimed at modulating the central pathways leading to TSD; this information may lead to the identification of principles that could refine the treatment of cancer and chronic infection by immune stimulation or autoimmunity and allograft rejection through immune tolerance.

  8. Development of a versatile oncolytic virus platform for local intra-tumoural expression of therapeutic transgenes.

    Science.gov (United States)

    Marino, Nalini; Illingworth, Sam; Kodialbail, Prithvi; Patel, Ashvin; Calderon, Hugo; Lear, Rochelle; Fisher, Kerry D; Champion, Brian R; Brown, Alice C N

    2017-01-01

    Oncolytic viruses which infect and kill tumour cells can also be genetically modified to express therapeutic genes that augment their anti-cancer activities. Modifying oncolytic viruses to produce effective cancer therapies is challenging as encoding transgenes often attenuates virus activity or prevents systemic delivery in patients due to the risk of off-target expression of transgenes in healthy tissues. To overcome these issues we aimed to generate a readily modifiable virus platform using the oncolytic adenovirus, enadenotucirev. Enadenotucirev replicates in human tumour cells but not cells from healthy tissues and can be delivered intravenously because it is stable in human blood. Here, the enadenotucirev genome was used to generate plasmids into which synthesised transgene cassettes could be directly cloned in a single step reaction. The platform enabled generation of panels of reporter viruses to identify cloning sites and transgene cassette designs where transgene expression could be linked to the virus life cycle. It was demonstrated using these viruses that encoded transgene proteins could be successfully expressed in tumour cells in vitro and tumours in vivo. The expression of transgenes did not impact either the oncolytic activity or selective properties of the virus. The effectiveness of this approach as a drug delivery platform for complex therapeutics was demonstrated by inserting multiple genes in the virus genome to encode full length anti-VEGF antibodies. Functional antibody could be synthesised and secreted from infected tumour cells without impacting the activity of the virus particle in terms of oncolytic potency, manufacturing yields or selectivity for tumour cells. In vivo, viral particles could be efficaciously delivered intravenously to disseminated orthotopic tumours.

  9. Expression of CCL19 from Oncolytic Vaccinia Enhances Immunotherapeutic Potential while Maintaining Oncolytic Activity

    Directory of Open Access Journals (Sweden)

    Jun Li

    2012-12-01

    Full Text Available Promising phase II clinical results have been reported recently for several oncolytic viral therapeutics, including strains based on vaccinia virus. One reason for this has been an increased appreciation of the critical therapeutic importance of the immune response raised by these viruses. However, the most commonly used approaches to enhance these immunotherapeutic effects in oncolytic viruses, typically though expression of cytokine transgenes, often also result in a reduction in oncolytic activity and premature clearance of the virotherapy from the tumor. Approaches that enhance the immunotherapeutic effects while maintaining oncolytic activity would therefore be beneficial. Here, it is demonstrated that the expression of the chemokine CCL19 (ELC from an oncolytic vaccinia virus (vvCCL19 results in increased antitumor effects in syngeneic mouse tumor models. This corresponded with increased t cell and dendritic cell infiltration into the tumor. However, vvCCL19 persisted in the tumor at equivalent levels to a control virus without CCL19, demonstrating that oncolytic activity was not curtailed. Instead, vvCCL19 was cleared rapidly and selectively from normal tissues and organs, indicating a potentially increased safety profile. The therapeutic activity of vvCCL19 could be further significantly increased through combination with adoptive transfer of therapeutic immune cells expressing CCR7, the receptor for CCL19. This approach therefore represents a means to increase the safety and therapeutic benefit of oncolytic viruses, used alone or in combination with immune cell therapies.

  10. Oncolytic myxoma virus: the path to clinic.

    Science.gov (United States)

    Chan, Winnie M; Rahman, Masmudur M; McFadden, Grant

    2013-09-06

    Many common neoplasms are still noncurative with current standards of cancer therapy. More therapeutic modalities need to be developed to significantly prolong the lives of patients and eventually cure a wider spectrum of cancers. Oncolytic virotherapy is one of the promising new additions to clinical cancer therapeutics. Successful oncolytic virotherapy in the clinic will be those strategies that best combine tumor cell oncolysis with enhanced immune responses against tumor antigens. The current candidate oncolytic viruses all share the common property that they are relatively nonpathogenic to humans, yet they have the ability to replicate selectively in human cancer cells and induce cancer regression by direct oncolysis and/or induction of improved anti-tumor immune responses. Many candidate oncolytic viruses are in various stages of clinical and preclinical development. One such preclinical candidate is myxoma virus (MYXV), a member of the Poxviridae family that, in its natural setting, exhibits a very restricted host range and is only pathogenic to European rabbits. Despite its narrow host range in nature, MYXV has been shown to productively infect various classes of human cancer cells. Several preclinical in vivo modeling studies have demonstrated that MYXV is an attractive and safe candidate oncolytic virus, and hence, MYXV is currently being developed as a potential therapeutic for several cancers, such as pancreatic cancer, glioblastoma, ovarian cancer, melanoma, and hematologic malignancies. This review highlights the preclinical cancer models that have shown the most promise for translation of MYXV into human clinical trials. Published by Elsevier Ltd.

  11. In vitro-generated interspecific recombinants between bovine herpesviruses 1 and 5 show attenuated replication characteristics and establish latency in the natural host

    Directory of Open Access Journals (Sweden)

    Thiry Julien

    2011-05-01

    Full Text Available Abstract Background Interspecific recombinant viruses R1ΔgC and R2ΔgI were isolated after in vitro co-infection with BoHV-1 and BoHV-5, two closely related alphaherpesviruses that infect cattle. The genetic characterization of R1ΔgC and R2ΔgI showed that they are composed of different sections of the parental genomes. The aim of this study was the characterization of the in vivo behavior of these recombinants in the natural host. Results Four groups of four 3-month-old calves of both genders were intranasally inoculated with either the recombinant or parental viruses. A control group of two animals was also included. Viral excretion and clinical signs were monitored after infection. Histopathological examination of the central nervous system (CNS was performed and the establishment of latency in trigeminal ganglia was analyzed by PCR. The humoral response was also evaluated using ELISA tests. Three out of four animals from the BoHV-5 infected group excreted virus for 4-10 days. Two calves shed R1ΔgC virus for one day. In R2ΔgI and BoHV-1.2ΔgCΔgI groups, infectious virus was isolated only after two or three blind passages. None of the infected animals developed neurological signs, although those infected with BoHV-5 showed histopathological evidence of viral infection. Latent viral DNA was detected in at least one calf from each infected group. Serum and/or mucosal antibodies were detected in all groups. Conclusion Both BoHV-1/-5 recombinants and the BoHV-1 parental strain are attenuated in calves, although they are able to replicate in animals at low rates and to establish latent infections.

  12. Attenuation of Recombinant Vesicular Stomatitis Virus-Human Immunodeficiency Virus Type 1 Vaccine Vectors by Gene Translocations and G Gene Truncation Reduces Neurovirulence and Enhances Immunogenicity in Mice▿

    Science.gov (United States)

    Cooper, David; Wright, Kevin J.; Calderon, Priscilla C.; Guo, Min; Nasar, Farooq; Johnson, J. Erik; Coleman, John W.; Lee, Margaret; Kotash, Cheryl; Yurgelonis, Irene; Natuk, Robert J.; Hendry, R. Michael; Udem, Stephen A.; Clarke, David K.

    2008-01-01

    Recombinant vesicular stomatitis virus (rVSV) has shown great potential as a new viral vector for vaccination. However, the prototypic rVSV vector described previously was found to be insufficiently attenuated for clinical evaluation when assessed for neurovirulence in nonhuman primates. Here, we describe the attenuation, neurovirulence, and immunogenicity of rVSV vectors expressing human immunodeficiency virus type 1 Gag. These rVSV vectors were attenuated by combinations of the following manipulations: N gene translocations (N4), G gene truncations (CT1 or CT9), noncytopathic M gene mutations (Mncp), and positioning of the gag gene into the first position of the viral genome (gag1). The resulting N4CT1-gag1, N4CT9-gag1, and MncpCT1-gag1 vectors demonstrated dramatically reduced neurovirulence in mice following direct intracranial inoculation. Surprisingly, in spite of a very high level of attenuation, the N4CT1-gag1 and N4CT9-gag1 vectors generated robust Gag-specific immune responses following intramuscular immunization that were equivalent to or greater than immune responses generated by the more virulent prototypic vectors. MncpCT1-gag1 also induced Gag-specific immune responses following intramuscular immunization that were equivalent to immune responses generated by the prototypic rVSV vector. Placement of the gag gene in the first position of the VSV genome was associated with increased in vitro expression of Gag protein, in vivo expression of Gag mRNA, and enhanced immunogenicity of the vector. These findings demonstrate that through directed manipulation of the rVSV genome, vectors that have reduced neurovirulence and enhanced immunogenicity can be made. PMID:17942549

  13. Oncolytic Immunotherapy: Where Are We Clinically?

    Directory of Open Access Journals (Sweden)

    Akseli Hemminki

    2014-01-01

    Full Text Available Following a century of preclinical and clinical work, oncolytic viruses are now proving themselves in randomized phase 3 trials. Interestingly, human data indicates that these agents have potent immunostimulatory activity, raising the possibility that the key consequence of oncolysis might be induction of antitumor immunity, especially in the context of viruses harboring immunostimulatory transgenes. While safety and efficacy of many types of oncolytic viruses, including adenovirus, herpes, reo, and vaccinia seem promising, few mechanisms of action studies have been performed with human substrates. Thus, the relative contribution of “pure” oncolysis, the immune response resulting from oncolysis, and the added benefit of adding a transgene remain poorly understood. Here, the available clinical data on oncolytic viruses is reviewed, with emphasis on immunological aspects.

  14. Virus, Oncolytic Virus and Human Prostate Cancer.

    Science.gov (United States)

    Liu, Guang Bin; Zhao, Liang; Zhang, Lifang; Zhao, Kong-Nan

    2017-01-01

    Prostate cancer (PCa), a disease, is characterized by abnormal cell growth in the prostate - a gland in the male reproductive system. Although older age and a family history of the disease have been recognized as the risk factors of PCa, the cause of this cancer remains unclear. Currently, PCa is one of the leading causes of cancer death among men of all races. In this review study, we first discuss the controversy of the contribution of virus infection to PCa, and subsequently summarize the development of oncolytic virotherapy for PCa in the past several years. Mounting evidence suggests that infections with various viruses are causally linked to PCa pathogenesis. Published studies have provided strong evidence that at least two viruses (RXMV and HPV) contribute to prostate tumourigenicity and impact on the survival of patients with malignant PCa. Traditional therapies including chemotherapy and radiotherapy are unable to distinguish cancer cells from normal cells, which are a significant drawback and leads to toxicities for PCa patients undergoing treatment. So far, few other options are available for treating patients with advanced PCa. For PCa treatment, oncolytic virotherapy appears to be much more attractive, which uses live viruses to selectively kill cancer cells. Oncolytic viruses can be genetically engineered to induce cancer cell lysis through virus replication and expression of cytotoxic proteins. Virotherapy is being developed to be a novel therapy for cancers, which uses oncotropic and oncolytic viruses with their abilities to find and destroy malignant cells in the body. As oncolytic viruses are a relatively new class of anti-cancer immunotherapy agents, several important barriers still exist on the road to the use of oncolytic viruses for PCa therapy. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  15. Oncolytic Virotherapy for Hematological Malignancies

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    Swarna Bais

    2012-01-01

    Full Text Available Hematological malignancies such as leukemias, lymphomas, multiple myeloma (MM, and the myelodysplastic syndromes (MDSs primarily affect adults and are difficult to treat. For high-risk disease, hematopoietic stem cell transplant (HCT can be used. However, in the setting of autologous HCT, relapse due to contamination of the autograft with cancer cells remains a major challenge. Ex vivo manipulations of the autograft to purge cancer cells using chemotherapies and toxins have been attempted. Because these past strategies lack specificity for malignant cells and often impair the normal hematopoietic stem and progenitor cells, prior efforts to ex vivo purge autografts have resulted in prolonged cytopenias and graft failure. The ideal ex vivo purging agent would selectively target the contaminating cancer cells while spare normal stem and progenitor cells and would be applied quickly without toxicities to the recipient. One agent which meets these criteria is oncolytic viruses. This paper details experimental progress with reovirus, myxoma virus, measles virus, vesicular stomatitis virus, coxsackievirus, and vaccinia virus as well as requirements for translation of these results to the clinic.

  16. Immunogenicity of viral vector, prime-boost SIV vaccine regimens in infant rhesus macaques: attenuated vesicular stomatitis virus (VSV) and modified vaccinia Ankara (MVA) recombinant SIV vaccines compared to live-attenuated SIV.

    Science.gov (United States)

    Van Rompay, Koen K A; Abel, Kristina; Earl, Patricia; Kozlowski, Pamela A; Easlick, Juliet; Moore, Joseph; Buonocore-Buzzelli, Linda; Schmidt, Kimberli A; Wilson, Robert L; Simon, Ian; Moss, Bernard; Rose, Nina; Rose, John; Marthas, Marta L

    2010-02-10

    In a previously developed infant macaque model mimicking HIV infection by breast-feeding, we demonstrated that intramuscular immunization with recombinant poxvirus vaccines expressing simian immunodeficiency virus (SIV) structural proteins provided partial protection against infection following oral inoculation with virulent SIV. In an attempt to further increase systemic but also local antiviral immune responses at the site of viral entry, we tested the immunogenicity of different orally administered, replicating vaccines. One group of newborn macaques received an oral prime immunization with a recombinant vesicular stomatitis virus expressing SIVmac239 gag, pol and env (VSV-SIVgpe), followed 2 weeks later by an intramuscular boost immunization with MVA-SIV. Another group received two immunizations with live-attenuated SIVmac1A11, administered each time both orally and intravenously. Control animals received mock immunizations or non-SIV VSV and MVA control vectors. Analysis of SIV-specific immune responses in blood and lymphoid tissues at 4 weeks of age demonstrated that both vaccine regimens induced systemic antibody responses and both systemic and local cell-mediated immune responses. The safety and immunogenicity of the VSV-SIVgpe+MVA-SIV immunization regimen described in this report provide the scientific incentive to explore the efficacy of this vaccine regimen against virulent SIV exposure in the infant macaque model. Copyright (c) 2009 Elsevier Ltd. All rights reserved.

  17. Recombinant Adeno-Associated Virus-Mediated Expression of Methamphetamine Antibody Attenuates Methamphetamine-Induced Hyperactivity in Mice

    OpenAIRE

    Yun-Hsiang Chen; Kuo-Jen Wu; Kuang-Lun Wu; Kun-Lieh Wu; Ho-Min Tsai; Mao-Liang Chen; Yi-Wei Chen; Wei Hsieh; Chun-Ming Lin; Yun Wang

    2017-01-01

    Methamphetamine (Meth) is one of the most frequently abused drugs worldwide. Recent studies have indicated that antibodies with high affinity for Meth reduce its pharmacological effects. The purpose of this study was to develop a technique for virus-based passive immunization against Meth effects. We generated a recombinant adeno-associated virus serotype-8 vector (AAV-MethAb) carrying the gene for a Meth-specific monoclonal antibody (MethAb). Infection of 293 cells with AAV-MethAb resulted i...

  18. In vivo Biodistribution of a Highly Attenuated Recombinant Vesicular Stomatitis Virus Expressing HIV-1 Gag Following Intramuscular, Intranasal, or Intravenous Inoculation

    Science.gov (United States)

    Johnson, J. Erik; Coleman, John W.; Kalyan, Narender K.; Calderon, Priscilla; Wright, Kevin J.; Obregon, Jennifer; Ogin-Wilson, Eleanor; Natuk, Robert J.; Clarke, David K.; Udem, Stephen A.; Cooper, David; Hendry, R. Michael

    2009-01-01

    Recombinant vesicular stomatitis viruses (rVSVs) are being developed as potential HIV-1 vaccine candidates. To characterize the in vivo replication and dissemination of rVSV vectors in mice, high doses of a highly attenuated vector expressing HIV-1 Gag, rVSVIN- N4CT9-Gag1, and a prototypic reference virus, rVSVIN-HIVGag5, were delivered intramuscularly (IM), intranasally (IN), or intravenously (IV). We used quantitative, real-time RT-PCR (Q-PCR) and standard plaque assays to measure the temporal dissemination of these viruses to various tissues. Following IM inoculation, both viruses were detected primarily at the injection site as well as in draining lymph nodes; neither virus induced significant weight loss, pathologic signs, or evidence of neuroinvasion. In contrast, following IN inoculation, the prototypic virus was detected in all tissues tested and caused significant weight loss leading to death. IN administration of rVSVIN- N4CT9-Gag1 resulted in detection in numerous tissues (brain, lung, nasal turbinates, and lymph nodes) albeit in significantly reduced levels, which caused little or no weight loss nor any mortality. Following IV inoculation, both prototypic and attenuated viruses were detected by Q-PCR in all tissues tested. In contrast to the prototype, rVSVIN-N4CT9-Gag1 viral loads were significantly lower in all organs tested, and no infectious virus was detected in the brain following IV inoculation, despite the presence of viral RNA. These studies demonstrated significant differences in the biodistribution patterns of and the associated pathogenicity engendered by the prototypic and attenuated vectors in a highly susceptible host. PMID:19428903

  19. Molecular imaging of oncolytic viral therapy

    Directory of Open Access Journals (Sweden)

    Dana Haddad

    2014-01-01

    Full Text Available Oncolytic viruses have made their mark on the cancer world as a potential therapeutic option, with the possible advantages of reduced side effects and strengthened treatment efficacy due to higher tumor selectivity. Results have been so promising, that oncolytic viral treatments have now been approved for clinical trials in several countries. However, clinical studies may benefit from the ability to noninvasively and serially identify sites of viral targeting via molecular imaging in order to provide safety, efficacy, and toxicity information. Furthermore, molecular imaging of oncolytic viral therapy may provide a more sensitive and specific diagnostic technique to detect tumor origin and, more importantly, presence of metastases. Several strategies have been investigated for molecular imaging of viral replication broadly categorized into optical and deep tissue imaging, utilizing several reporter genes encoding for fluorescence proteins, conditional enzymes, and membrane protein and transporters. Various imaging methods facilitate molecular imaging, including computer tomography, magnetic resonance imaging, positron emission tomography, single photon emission CT, gamma-scintigraphy, and photoacoustic imaging. In addition, several molecular probes are used for medical imaging, which act as targeting moieties or signaling agents. This review will explore the preclinical and clinical use of in vivo molecular imaging of replication-competent oncolytic viral therapy.

  20. Using Oncolytic Viruses to Treat Cancer

    Science.gov (United States)

    Cancer treatments known as oncolytic viruses are being tested in clinical trials, and one, T-VEC or Imlygic®, has been approved by the FDA. Research now suggests that these treatments work not only by infecting and killing tumor cells, but that they may also be a form of cancer immunotherapy.

  1. First Oncolytic Viral Therapy for Melanoma.

    Science.gov (United States)

    Poh, Alissa

    2016-01-01

    The FDA has approved talimogene laherparepvec, or T-VEC, to treat surgically unresectable skin and lymph node lesions in patients with advanced melanoma. T-VEC is the first oncolytic viral therapy to gain regulatory endorsement, based on data from the OPTiM study. ©2016 American Association for Cancer Research.

  2. Retargeting of viruses to generate oncolytic agents

    NARCIS (Netherlands)

    Verheije, M.H.; Rottier, P.J.M.

    2012-01-01

    Oncolytic virus therapy is based on the ability of viruses to effectively infect and kill tumor cells without destroying the normal tissues. While some viruses seem to have a natural preference for tumor cells, most viruses require the modification of their tropism to specifically enter and

  3. Tumor-Localized Secretion of Soluble PD1 Enhances Oncolytic Virotherapy.

    Science.gov (United States)

    Bartee, Mee Y; Dunlap, Katherine M; Bartee, Eric

    2017-06-01

    Oncolytic virotherapy represents an attractive option for the treatment of a variety of aggressive or refractory tumors. While this therapy is effective at rapidly debulking directly injected tumor masses, achieving complete eradication of established disease has proven difficult. One method to overcome this challenge is to use oncolytic viruses to induce secondary antitumor immune responses. Unfortunately, while the initial induction of these immune responses is typically robust, their subsequent efficacy is often inhibited through a variety of immunoregulatory mechanisms, including the PD1/PDL1 T-cell checkpoint pathway. To overcome this inhibition, we generated a novel recombinant myxoma virus (vPD1), which inhibits the PD1/PDL1 pathway specifically within the tumor microenvironment by secreting a soluble form of PD1 from infected cells. This virus both induced and maintained antitumor CD8(+) T-cell responses within directly treated tumors and proved safer and more effective than combination therapy using unmodified myxoma and systemic αPD1 antibodies. Localized vPD1 treatment combined with systemic elimination of regulatory T cells had potent synergistic effects against metastatic disease that was already established in secondary solid organs. These results demonstrate that tumor-localized inhibition of the PD1/PDL1 pathway can significantly improve outcomes during oncolytic virotherapy. Furthermore, they establish a feasible path to translate these findings against clinically relevant disease. Cancer Res; 77(11); 2952-63. ©2017 AACR. ©2017 American Association for Cancer Research.

  4. Oncolytic Vesicular Stomatitis Virus in an Immunocompetent Model of MUC1-Positive or MUC1-Null Pancreatic Ductal Adenocarcinoma

    Science.gov (United States)

    Hastie, Eric; Besmer, Dahlia M.; Shah, Nirav R.; Murphy, Andrea M.; Moerdyk-Schauwecker, Megan; Molestina, Carlos; Roy, Lopamudra Das; Curry, Jennifer M.; Mukherjee, Pinku

    2013-01-01

    Vesicular stomatitis virus (VSV) is a promising oncolytic agent against various malignancies. Here, for the first time, we tested VSV in vitro and in vivo in a clinically relevant, immunocompetent mouse model of pancreatic ductal adenocarcinoma (PDA). Our system allows the study of virotherapy against PDA in the context of overexpression (80% of PDA patients) or no expression of human mucin 1 (MUC1), a major marker for poor prognosis in patients. In vitro, we tested three VSV recombinants, wild-type VSV, VSV-green fluorescent protein (VSV-GFP), and a safe oncolytic VSV-ΔM51-GFP, against five mouse PDA cell lines that either expressed human MUC1 or were MUC1 null. All viruses demonstrated significant oncolytic abilities independent of MUC1 expression, although VSV-ΔM51-GFP was somewhat less effective in two PDA cell lines. In vivo administration of VSV-ΔM51-GFP resulted in significant reduction of tumor growth for tested mouse PDA xenografts (+MUC1 or MUC1 null), and antitumor efficacy was further improved when the virus was combined with the chemotherapeutic drug gemcitabine. The antitumor effect was transient in all tested groups. The developed system can be used to study therapies involving various oncolytic viruses and chemotherapeutics, with the goal of inducing tumor-specific immunity while preventing premature virus clearance. PMID:23864625

  5. Oncolytic vesicular stomatitis virus in an immunocompetent model of MUC1-positive or MUC1-null pancreatic ductal adenocarcinoma.

    Science.gov (United States)

    Hastie, Eric; Besmer, Dahlia M; Shah, Nirav R; Murphy, Andrea M; Moerdyk-Schauwecker, Megan; Molestina, Carlos; Roy, Lopamudra Das; Curry, Jennifer M; Mukherjee, Pinku; Grdzelishvili, Valery Z

    2013-09-01

    Vesicular stomatitis virus (VSV) is a promising oncolytic agent against various malignancies. Here, for the first time, we tested VSV in vitro and in vivo in a clinically relevant, immunocompetent mouse model of pancreatic ductal adenocarcinoma (PDA). Our system allows the study of virotherapy against PDA in the context of overexpression (80% of PDA patients) or no expression of human mucin 1 (MUC1), a major marker for poor prognosis in patients. In vitro, we tested three VSV recombinants, wild-type VSV, VSV-green fluorescent protein (VSV-GFP), and a safe oncolytic VSV-ΔM51-GFP, against five mouse PDA cell lines that either expressed human MUC1 or were MUC1 null. All viruses demonstrated significant oncolytic abilities independent of MUC1 expression, although VSV-ΔM51-GFP was somewhat less effective in two PDA cell lines. In vivo administration of VSV-ΔM51-GFP resulted in significant reduction of tumor growth for tested mouse PDA xenografts (+MUC1 or MUC1 null), and antitumor efficacy was further improved when the virus was combined with the chemotherapeutic drug gemcitabine. The antitumor effect was transient in all tested groups. The developed system can be used to study therapies involving various oncolytic viruses and chemotherapeutics, with the goal of inducing tumor-specific immunity while preventing premature virus clearance.

  6. Oncolytic and immunologic cancer therapy with GM-CSF-armed vaccinia virus of Tian Tan strain Guang9.

    Science.gov (United States)

    Deng, Lili; Fan, Jun; Guo, Mingming; Huang, Biao

    2016-03-28

    Targeted oncolytic vaccinia viruses are being developed as a novel strategy in cancer therapy. Arming vaccinia viruses with immunostimulatory cytokines can enhance antitumor efficacy. Such engineered oncolytic viruses, like JX-594, a Wyeth strain vaccinia virus modified with human granulocyte-macrophage colony-stimulating factor (GM-CSF), have shown promising results and have proceeded rapidly in clinical trials. However, the oncolytic potential of the Chinese vaccine strain Tian Tan (VTT) has not been explored. In this study, we constructed a targeted oncolytic vaccinia virus of Tian Tan strain Guang9 (VG9) expressing murine GM-CSF (VG9-GMCSF) and evaluated the antitumor effect of this recombinant vaccinia virus in a murine melanoma model. In vitro, viral replication and cytotoxicity of VG9-GMCSF was as potent as VG9; in vivo, VG9-GMCSF significantly inhibited the growth of subcutaneously implanted melanoma tumors, prolonged the survival of tumor-bearing mice, and produced an antitumor cytotoxic response. Such antitumor effect may be due to the lytic nature of virus as well as the stimulation of immune activity by GM-CSF production. Our results indicate that VG9-GMCSF induces strong tumoricidal activity, providing a potential therapeutic strategy for combating cancer. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  7. Oncolytic viruses: a new class of immunotherapy drugs.

    Science.gov (United States)

    Kaufman, Howard L; Kohlhapp, Frederick J; Zloza, Andrew

    2015-09-01

    Oncolytic viruses represent a new class of therapeutic agents that promote anti-tumour responses through a dual mechanism of action that is dependent on selective tumour cell killing and the induction of systemic anti-tumour immunity. The molecular and cellular mechanisms of action are not fully elucidated but are likely to depend on viral replication within transformed cells, induction of primary cell death, interaction with tumour cell antiviral elements and initiation of innate and adaptive anti-tumour immunity. A variety of native and genetically modified viruses have been developed as oncolytic agents, and the approval of the first oncolytic virus by the US Food and Drug Administration (FDA) is anticipated in the near future. This Review provides a comprehensive overview of the basic biology supporting oncolytic viruses as cancer therapeutic agents, describes oncolytic viruses in advanced clinical trials and discusses the unique challenges in the development of oncolytic viruses as a new class of drugs for the treatment of cancer.

  8. Talimogene Laherparepvec (T-VEC) and Other Oncolytic Viruses for the Treatment of Melanoma.

    Science.gov (United States)

    Bommareddy, Praveen K; Patel, Anand; Hossain, Saamia; Kaufman, Howard L

    2017-02-01

    Many mammalian viruses have properties that can be commandeered for the treatment of cancer. These characteristics include preferential infection and replication in tumor cells, the initiation of tumor cell lysis, and the induction of innate and adaptive anti-tumor immunity. Furthermore, viruses can be genetically engineered to reduce pathogenicity and increase immunogenicity resulting in minimally toxic therapeutic agents. Talimogene laherparepvec (T-VEC; Imlygic™), is a genetically modified herpes simplex virus, type 1, and is the first oncolytic virus therapy to be approved for the treatment of advanced melanoma by the US FDA. T-VEC is attenuated by the deletion of the herpes neurovirulence viral genes and enhanced for immunogenicity by the deletion of the viral ICP47 gene. Immunogenicity is further supported by expression of the human granulocyte-macrophage colony-stimulating factor (GM-CSF) gene, which helps promote the priming of T cell responses. T-VEC demonstrated significant improvement in durable response rate, objective response rate, and progression-free survival in a randomized phase III clinical trial for patients with advanced melanoma. This review will discuss the optimal selection of patients for such treatment and describe how therapy is optimally delivered. We will also discuss future directions for oncolytic virus immunotherapy, which will likely include combination T-VEC clinical trials, expansion of T-VEC to other types of non-melanoma skin cancers, and renewed efforts at oncolytic virus drug development with other viruses.

  9. Reovirus FAST Protein Enhances Vesicular Stomatitis Virus Oncolytic Virotherapy in Primary and Metastatic Tumor Models

    Directory of Open Access Journals (Sweden)

    Fabrice Le Boeuf

    2017-09-01

    Full Text Available The reovirus fusion-associated small transmembrane (FAST proteins are the smallest known viral fusogens (∼100–150 amino acids and efficiently induce cell-cell fusion and syncytium formation in multiple cell types. Syncytium formation enhances cell-cell virus transmission and may also induce immunogenic cell death, a form of apoptosis that stimulates immune recognition of tumor cells. These properties suggest that FAST proteins might serve to enhance oncolytic virotherapy. The oncolytic activity of recombinant VSVΔM51 (an interferon-sensitive vesicular stomatitis virus [VSV] mutant encoding the p14 FAST protein (VSV-p14 was compared with a similar construct encoding GFP (VSV-GFP in cell culture and syngeneic BALB/c tumor models. Compared with VSV-GFP, VSV-p14 exhibited increased oncolytic activity against MCF-7 and 4T1 breast cancer spheroids in culture and reduced primary 4T1 breast tumor growth in vivo. VSV-p14 prolonged survival in both primary and metastatic 4T1 breast cancer models, and in a CT26 metastatic colon cancer model. As with VSV-GFP, VSV-p14 preferentially replicated in vivo in tumors and was cleared rapidly from other sites. Furthermore, VSV-p14 increased the numbers of activated splenic CD4, CD8, natural killer (NK, and natural killer T (NKT cells, and increased the number of activated CD4 and CD8 cells in tumors. FAST proteins may therefore provide a multi-pronged approach to improving oncolytic virotherapy via syncytium formation and enhanced immune stimulation.

  10. Critical analysis of an oncolytic herpesvirus encoding granulocyte-macrophage colony stimulating factor for the treatment of malignant melanoma

    Directory of Open Access Journals (Sweden)

    Hughes T

    2014-01-01

    Full Text Available Tasha Hughes,1 Robert S Coffin,2 Caroline E Lilley,2 Rafael Ponce,2 Howard L Kaufman1 1Departments of General Surgery and Immunology and Microbiology, Rush University Medical Center, Chicago IL, 2BioVex, Inc, a subsidiary of Amgen, Inc, Sherman Oaks, CA, USA Abstract: Oncolytic viruses that selectively lyse tumor cells with minimal damage to normal cells are a new area of therapeutic development in oncology. An attenuated herpesvirus encoding the granulocyte-macrophage colony stimulating factor (GM-CSF, known as talimogene laherparepvec (T-VEC, has been identified as an attractive oncolytic virus for cancer therapy based on preclinical tumor studies and results from early-phase clinical trials and a large randomized Phase III study in melanoma. In this review, we discuss the basic biology of T-VEC, describe the role of GM-CSF as an immune adjuvant, summarize the preclinical data, and report the outcomes of published clinical trials using T-VEC. The emerging data suggest that T-VEC is a safe and potentially effective antitumor therapy in malignant melanoma and represents the first oncolytic virus to demonstrate therapeutic activity against human cancer in a randomized, controlled Phase III study. Keywords: granulocyte-macrophage colony stimulating factor, herpesvirus, melanoma, oncolytic virus, treatment

  11. Expression of interferon gamma by a recombinant rabies virus strongly attenuates the pathogenicity of the virus via induction of type I interferon.

    Science.gov (United States)

    Barkhouse, Darryll A; Garcia, Samantha A; Bongiorno, Emily K; Lebrun, Aurore; Faber, Milosz; Hooper, D Craig

    2015-01-01

    Previous animal model experiments have shown a correlation between interferon gamma (IFN-γ) expression and both survival from infection with attenuated rabies virus (RABV) and reduction of neurological sequelae. Therefore, we hypothesized that rapid production of murine IFN-γ by the rabies virus itself would induce a more robust antiviral response than would occur naturally in mice. To test this hypothesis, we used reverse engineering to clone the mouse IFN-γ gene into a pathogenic rabies virus backbone, SPBN, to produce the recombinant rabies virus designated SPBNγ. Morbidity and mortality were monitored in mice infected intranasally with SPBNγ or SPBN(-) control virus to determine the degree of attenuation caused by the expression of IFN-γ. Incorporation of IFN-γ into the rabies virus genome highly attenuated the virus. SPBNγ has a 50% lethal dose (LD50) more than 100-fold greater than SPBN(-). In vitro and in vivo mouse experiments show that SPBNγ infection enhances the production of type I interferons. Furthermore, knockout mice lacking the ability to signal through the type I interferon receptor (IFNAR(-/-)) cannot control the SPBNγ infection and rapidly die. These data suggest that IFN-γ production has antiviral effects in rabies, largely due to the induction of type I interferons. Survival from rabies is dependent upon the early control of virus replication and spread. Once the virus reaches the central nervous system (CNS), this becomes highly problematic. Studies of CNS immunity to RABV have shown that control of replication begins at the onset of T cell entry and IFN-γ production in the CNS prior to the appearance of virus-neutralizing antibodies. Moreover, antibody-deficient mice are able to control but not clear attenuated RABV from the CNS. We find here that IFN-γ triggers the early production of type I interferons with the expected antiviral effects. We also show that engineering a lethal rabies virus to express IFN-γ directly in the

  12. Trial Watch-Oncolytic viruses and cancer therapy.

    Science.gov (United States)

    Pol, Jonathan; Buqué, Aitziber; Aranda, Fernando; Bloy, Norma; Cremer, Isabelle; Eggermont, Alexander; Erbs, Philippe; Fucikova, Jitka; Galon, Jérôme; Limacher, Jean-Marc; Preville, Xavier; Sautès-Fridman, Catherine; Spisek, Radek; Zitvogel, Laurence; Kroemer, Guido; Galluzzi, Lorenzo

    2016-02-01

    Oncolytic virotherapy relies on the administration of non-pathogenic viral strains that selectively infect and kill malignant cells while favoring the elicitation of a therapeutically relevant tumor-targeting immune response. During the past few years, great efforts have been dedicated to the development of oncolytic viruses with improved specificity and potency. Such an intense wave of investigation has culminated this year in the regulatory approval by the US Food and Drug Administration (FDA) of a genetically engineered oncolytic viral strain for use in melanoma patients. Here, we summarize recent preclinical and clinical advances in oncolytic virotherapy.

  13. Attenuation of skeletal muscle wasting with recombinant human growth hormone secreted from a tissue-engineered bioartificial muscle

    Science.gov (United States)

    Vandenburgh, H.; Del Tatto, M.; Shansky, J.; Goldstein, L.; Russell, K.; Genes, N.; Chromiak, J.; Yamada, S.

    1998-01-01

    Skeletal muscle wasting is a significant problem in elderly and debilitated patients. Growth hormone (GH) is an anabolic growth factor for skeletal muscle but is difficult to deliver in a therapeutic manner by injection owing to its in vivo instability. A novel method is presented for the sustained secretion of recombinant human GH (rhGH) from genetically modified skeletal muscle implants, which reduces host muscle wasting. Proliferating murine C2C12 skeletal myoblasts stably transduced with the rhGH gene were tissue engineered in vitro into bioartificial muscles (C2-BAMs) containing organized postmitotic myofibers secreting 3-5 microg of rhGH/day in vitro. When implanted subcutaneously into syngeneic mice, C2-BAMs delivered a sustained physiologic dose of 2.5 to 11.3 ng of rhGH per milliliter of serum. rhGH synthesized and secreted by the myofibers was in the 22-kDa monomeric form and was biologically active, based on downregulation of a GH-sensitive protein synthesized in the liver. Skeletal muscle disuse atrophy was induced in mice by hindlimb unloading, causing the fast plantaris and slow soleus muscles to atrophy by 21 to 35% ( muscle-wasting disorders.

  14. Truncated recombinant human SP-D attenuates emphysema and type II cell changes in SP-D deficient mice.

    Science.gov (United States)

    Knudsen, Lars; Ochs, Matthias; Mackay, Rosemarie; Townsend, Paul; Deb, Roona; Mühlfeld, Christian; Richter, Joachim; Gilbert, Fabian; Hawgood, Samuel; Reid, Kenneth; Clark, Howard

    2007-10-03

    Surfactant protein D (SP-D) deficient mice develop emphysema-like pathology associated with focal accumulations of foamy alveolar macrophages, an excess of surfactant phospholipids in the alveolar space and both hypertrophy and hyperplasia of alveolar type II cells. These findings are associated with a chronic inflammatory state. Treatment of SP-D deficient mice with a truncated recombinant fragment of human SP-D (rfhSP-D) has been shown to decrease the lipidosis and alveolar macrophage accumulation as well as production of proinflammatory chemokines. The aim of this study was to investigate if rfhSP-D treatment reduces the structural abnormalities in parenchymal architecture and type II cells characteristic of SP-D deficiency. SP-D knock-out mice, aged 3 weeks, 6 weeks and 9 weeks were treated with rfhSP-D for 9, 6 and 3 weeks, respectively. All mice were sacrificed at age 12 weeks and compared to both PBS treated SP-D deficient and wild-type groups. Lung structure was quantified by design-based stereology at the light and electron microscopic level. Emphasis was put on quantification of emphysema, type II cell changes and intracellular surfactant. Data were analysed with two sided non-parametric Mann-Whitney U-test. After 3 weeks of treatment, alveolar number was higher and mean alveolar size was smaller compared to saline-treated SP-D knock-out controls. There was no significant difference concerning these indices of pulmonary emphysema within rfhSP-D treated groups. Type II cell number and size were smaller as a consequence of treatment. The total volume of lamellar bodies per type II cell and per lung was smaller after 6 weeks of treatment. Treatment of SP-D deficient mice with rfhSP-D leads to a reduction in the degree of emphysema and a correction of type II cell hyperplasia and hypertrophy. This supports the concept that rfhSP-D might become a therapeutic option in diseases that are characterized by decreased SP-D levels in the lung.

  15. Truncated recombinant human SP-D attenuates emphysema and type II cell changes in SP-D deficient mice

    Directory of Open Access Journals (Sweden)

    Mühlfeld Christian

    2007-10-01

    Full Text Available Abstract Background Surfactant protein D (SP-D deficient mice develop emphysema-like pathology associated with focal accumulations of foamy alveolar macrophages, an excess of surfactant phospholipids in the alveolar space and both hypertrophy and hyperplasia of alveolar type II cells. These findings are associated with a chronic inflammatory state. Treatment of SP-D deficient mice with a truncated recombinant fragment of human SP-D (rfhSP-D has been shown to decrease the lipidosis and alveolar macrophage accumulation as well as production of proinflammatory chemokines. The aim of this study was to investigate if rfhSP-D treatment reduces the structural abnormalities in parenchymal architecture and type II cells characteristic of SP-D deficiency. Methods SP-D knock-out mice, aged 3 weeks, 6 weeks and 9 weeks were treated with rfhSP-D for 9, 6 and 3 weeks, respectively. All mice were sacrificed at age 12 weeks and compared to both PBS treated SP-D deficient and wild-type groups. Lung structure was quantified by design-based stereology at the light and electron microscopic level. Emphasis was put on quantification of emphysema, type II cell changes and intracellular surfactant. Data were analysed with two sided non-parametric Mann-Whitney U-test. Main Results After 3 weeks of treatment, alveolar number was higher and mean alveolar size was smaller compared to saline-treated SP-D knock-out controls. There was no significant difference concerning these indices of pulmonary emphysema within rfhSP-D treated groups. Type II cell number and size were smaller as a consequence of treatment. The total volume of lamellar bodies per type II cell and per lung was smaller after 6 weeks of treatment. Conclusion Treatment of SP-D deficient mice with rfhSP-D leads to a reduction in the degree of emphysema and a correction of type II cell hyperplasia and hypertrophy. This supports the concept that rfhSP-D might become a therapeutic option in diseases that are

  16. Oncolytic Viruses in Cancer Treatment: A Review.

    Science.gov (United States)

    Lawler, Sean E; Speranza, Maria-Carmela; Cho, Choi-Fong; Chiocca, E Antonio

    2017-06-01

    Oncolytic viruses (OVs) are emerging as important agents in cancer treatment. Oncolytic viruses offer the attractive therapeutic combination of tumor-specific cell lysis together with immune stimulation, therefore acting as potential in situ tumor vaccines. Moreover, OVs can be engineered for optimization of tumor selectivity and enhanced immune stimulation and can be readily combined with other agents. The effectiveness of OVs has been demonstrated in many preclinical studies and recently in humans, with US Food and Drug Administration approval of the oncolytic herpesvirus talimogene laherparepvec in advanced melanoma, a major breakthrough for the field. Thus, the OV approach to cancer therapy is becoming more interesting for scientists, clinicians, and the public. The main purpose of this review is to give a basic overview of OVs in clinical development and provide a description of the current status of clinical trials. In 2016 approximately 40 clinical trials are recruiting patients, using a range of OVs in multiple cancer types. There are also many more trials in the planning stages. Therefore, we are now in the most active period of clinical OV studies in the history of the field. There are several OVs currently being tested with many additional engineered derivatives. In OV clinical trials, there are a number of specific areas that should be considered, including viral pharmacokinetics and pharmacodynamics, potential toxic effects, and monitoring of the patients' immune status. Clinical development of OVs is increasingly focused on their immune stimulatory properties, which may work synergistically with immune checkpoint inhibitors and other strategies in the treatment of human cancer. Oncolytic viruses are an active area of clinical research. The ability of these agents to harness antitumor immunity appears to be key for their success. Combinatorial studies with immune checkpoint blockade have started and the results are awaited with great interest.

  17. First oncolytic virus approved for melanoma immunotherapy.

    Science.gov (United States)

    Pol, Jonathan; Kroemer, Guido; Galluzzi, Lorenzo

    On 2015, October 27th, the US Food and Drug Administration (FDA) has officially approved talimogene laherparepvec (T-VEC, also known as OncoVEX(GM-CSF)) for use in melanoma patients with injectable but non-resectable lesions in the skin and lymph nodes. T-VEC (which is commercialized by Amgen, Inc. under the name of Imlygic®) becomes therefore the first oncolytic virus approved for cancer therapy in the US.

  18. HVJ-AVE liposome-mediated Tissue Factor Pathway Inhibitor (TFPI) gene transfer with recombinant TFPI (rTFPI) irrigation attenuates restenosis in atherosclerotic arteries.

    Science.gov (United States)

    Yin, Xinhua; Fu, Yu; Yutani, Chikao; Ikeda, Yoshihiko; Enjyoji, Keiichi; Kato, Hisao

    2009-06-26

    In this study, we investigate whether the combination of HVJ-AVE liposome-mediated TFPI gene transfer and recombinant TFPI (rTFPI) irrigation would reduce restenosis safely and more effectively. The results indicated that at 4 weeks after angioplasty, the MLD, EELA, IELA and LA of TFPI group and rTFPI group were markedly greater than those of the control groups, and those in the combination group were even greater. The mean IA, I/M, and the percentage of stenosis in TFPI gene group and rTFPI group were significantly reduced compared with control groups, and those in the combination group were even further reduced. Thrombosis in the TFPI gene group, rTFPI group and combination group was significantly reduced compared with the other control groups. The systemic coagulation status of treated animals was not significantly changed and no toxicity was observed in each group. So combination of TFPI gene transfer using HVJ-AVE liposomes and rTFPI irrigation could inhibit thrombosis and neointimal hyperplasia, and attenuate vascular remodeling and luminal stenosis more effectively than using each method alone. The combination method may be a more effective and safe strategy for the prevention of restenosis after angioplasty in humans.

  19. Oncolytic virotherapy: the questions and the promise

    Directory of Open Access Journals (Sweden)

    Aurelian L

    2013-06-01

    Full Text Available Laure Aurelian Department of Pharmacology, University of Maryland School of Medicine, Baltimore, MD, USA Abstract: Oncolytic virotherapy is a new strategy to reduce tumor burden through selective virus replication in rapidly proliferating cells. Oncolytic viruses are members of at least ten virus families, each with its advantages and disadvantages. Here, I briefly review the recent advances and key challenges, as exemplified by the best-studied platforms. Recent advances include preclinical proof of feasibility, clinical evidence of tolerability and effectiveness, and the development of new strategies to improve efficacy. These include engineered tumor selectivity and expression of antitumorigenic genes that could function independently of virus replication, identification of combinatorial therapies that accelerate intratumoral virus propagation, and modification of immune responses and vascular delivery for treatment of metastatic disease. Key challenges are to select “winners” from the distinct oncolytic platforms that can stimulate anti-cancer immunity without affecting virus replication and can lyse cancer stem cells, which are most likely responsible for tumor maintenance, aggressiveness, and recurrence. Preventing the emergence of resistant tumor cells during virotherapy through the activation of multiple death pathways, the development of a better understanding of the mechanisms of cancer stem-cell lysis, and the development of more meaningful preclinical animal models are additional challenges for the next-generation of engineered viruses. Keywords: tumor cell lysis, virus replication, tumor selectivity, programmed cell death, immune response

  20. Oncolytic viruses: a step into cancer immunotherapy

    Directory of Open Access Journals (Sweden)

    Pol JG

    2011-12-01

    Full Text Available Jonathan G Pol, Julien Rességuier, Brian D LichtyMcMaster Immunology Research Centre, Department of Pathology and Molecular Medicine, McMaster University, Hamilton, Ontario, CanadaAbstract: Oncolytic virotherapy is currently under investigation in phase I–III clinical trials for approval as a new cancer treatment. Oncolytic viruses (OVs selectively infect, replicate in, and kill tumor cells. For a long time, the therapeutic efficacy was thought to depend on the direct viral oncolysis (virocentric view. The host immune system was considered as a brake that impaired virus delivery and spread. Attention was paid primarily to approaches enhancing virus tumor selectivity and cytotoxicity and/or that limited antiviral responses. Thinking has changed over the past few years with the discovery that OV therapy was also inducing indirect oncolysis mechanisms. Among them, induction of an antitumor immunity following OV injection appeared to be a key factor for an efficient therapeutic activity (immunocentric view. Indeed, tumor-specific immune cells persist post-therapy and can search and destroy any tumor cells that escape the OVs, and thus immune memory may prevent relapse of the disease. Various strategies, which are summarized in this manuscript, have been developed to enhance the efficacy of OV therapy with a focus on its immunotherapeutic aspects. These include genetic engineering and combination with existing cancer treatments. Several are currently being evaluated in human patients and already display promising efficacy.Keywords: oncolytic virus, cancer immunotherapy, tumor antigen, cancer vaccine, combination strategies

  1. Antitumor activity of an oncolytic adenoviral-CD40 ligand (CD154) transgene construct in human breast cancer cells.

    Science.gov (United States)

    Gomes, Erica M; Rodrigues, Margret S; Phadke, Anagha P; Butcher, Lindsay D; Starling, Cherry; Chen, Salina; Chang, Dongkun; Hernandez-Alcoceba, Ruben; Newman, Joseph T; Stone, Marvin J; Tong, Alex W

    2009-02-15

    CD40 ligand (CD40L, CD154) plays a central role in immunoregulation and also directly modulates epithelial cell growth and differentiation. We previously showed that the CD40 receptor is commonly expressed in primary breast cancer tissues. In this proof-of-principle study, we examined the breast cancer growth-regulatory activities of an oncolytic adenoviral construct carrying the CD40L transgene (AdEHCD40L). In vitro and in vivo evaluations were carried out on AdEHCD40L to validate selective viral replication and CD40L transgene activity in hypoxia inducing factor-1alpha and estrogen receptor-expressing human breast cancer cells. AdEHCD40L inhibited the in vitro growth of CD40+ human breast cancer lines (T-47D, MDA-MB-231, and BT-20) by up to 80% at a low multiplicity of infection of 1. Incorporation of the CD40L transgene reduced the effective dose needed to achieve 50% growth inhibition (ED50) by approximately 10-fold. In contrast, viral and transgene expression of AdEHCD40L, as well its cytotoxicity, was markedly attenuated in nonmalignant cells. Intratumoral injections with AdEHCD40L reduced preexisting MDA-MB-231 xenograft growth in severe combined immunodeficient mice by >99% and was significantly more effective (P<0.003) than parental virus AdEH (69%) or the recombinant CD40L protein (49%). This enhanced antitumor activity correlated with cell cycle blockade and increased apoptosis in AdEHCD40L-infected tumor cells. These novel findings, together with the previously known immune-activating features of CD40L, support the potential applicability of AdEHCD40L for experimental treatment of human breast cancer.

  2. Combining Oncolytic Virotherapy with p53 Tumor Suppressor Gene Therapy

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    Christian Bressy

    2017-06-01

    Full Text Available Oncolytic virus (OV therapy utilizes replication-competent viruses to kill cancer cells, leaving non-malignant cells unharmed. With the first U.S. Food and Drug Administration-approved OV, dozens of clinical trials ongoing, and an abundance of translational research in the field, OV therapy is poised to be one of the leading treatments for cancer. A number of recombinant OVs expressing a transgene for p53 (TP53 or another p53 family member (TP63 or TP73 were engineered with the goal of generating more potent OVs that function synergistically with host immunity and/or other therapies to reduce or eliminate tumor burden. Such transgenes have proven effective at improving OV therapies, and basic research has shown mechanisms of p53-mediated enhancement of OV therapy, provided optimized p53 transgenes, explored drug-OV combinational treatments, and challenged canonical roles for p53 in virus-host interactions and tumor suppression. This review summarizes studies combining p53 gene therapy with replication-competent OV therapy, reviews preclinical and clinical studies with replication-deficient gene therapy vectors expressing p53 transgene, examines how wild-type p53 and p53 modifications affect OV replication and anti-tumor effects of OV therapy, and explores future directions for rational design of OV therapy combined with p53 gene therapy.

  3. Combining Oncolytic Virotherapy with p53 Tumor Suppressor Gene Therapy.

    Science.gov (United States)

    Bressy, Christian; Hastie, Eric; Grdzelishvili, Valery Z

    2017-06-16

    Oncolytic virus (OV) therapy utilizes replication-competent viruses to kill cancer cells, leaving non-malignant cells unharmed. With the first U.S. Food and Drug Administration-approved OV, dozens of clinical trials ongoing, and an abundance of translational research in the field, OV therapy is poised to be one of the leading treatments for cancer. A number of recombinant OVs expressing a transgene for p53 (TP53) or another p53 family member (TP63 or TP73) were engineered with the goal of generating more potent OVs that function synergistically with host immunity and/or other therapies to reduce or eliminate tumor burden. Such transgenes have proven effective at improving OV therapies, and basic research has shown mechanisms of p53-mediated enhancement of OV therapy, provided optimized p53 transgenes, explored drug-OV combinational treatments, and challenged canonical roles for p53 in virus-host interactions and tumor suppression. This review summarizes studies combining p53 gene therapy with replication-competent OV therapy, reviews preclinical and clinical studies with replication-deficient gene therapy vectors expressing p53 transgene, examines how wild-type p53 and p53 modifications affect OV replication and anti-tumor effects of OV therapy, and explores future directions for rational design of OV therapy combined with p53 gene therapy.

  4. Factor XIII and tranexamic acid but not recombinant factor VIIa attenuate tissue plasminogen activator-induced hyperfibrinolysis in human whole blood.

    Science.gov (United States)

    Dirkmann, Daniel; Görlinger, Klaus; Gisbertz, Caroline; Dusse, Fabian; Peters, Jürgen

    2012-06-01

    Hyperfibrinolysis is a pathological state that often results in depletion of coagulation factors and platelets and can contribute to bleeding. Factor XIII (FXIII) and thrombin activatable fibrinolysis inhibitor have key roles in protecting clots against fibrinolysis. We tested the hypotheses that FXIII concentrate, prothrombin complex concentrate (PCC), recombinant factor VIIa (rFVIIa), and tranexamic acid (TA) inhibit fibrinolysis to different degrees, and that platelets contribute to antifibrinolysis. Hyperfibrinolysis was induced by addition of recombinant tissue plasminogen activator (r-tPA) (final concentration: 100 ng · mL(-1)) to citrated whole blood obtained from 13 healthy volunteers. To assess inhibition of fibrinolysis, we added to the assays FXIII-A(2)B(2) (0.42 U · mL(-1)), PCC (0.42 U · mL(-1)), rFVIIa (final concentration: 1.6 μg · mL(-1)), TA (final concentration: 0.33 mg · mL(-1)), or saline. Coagulation was analyzed by rotational thromboelastometry (ROTEM®) using the clot lysis index (CLI) after 45 and 60 minutes in extrinsically activated assays, with (FIBTEM®) and without (EXTEM®) inhibition of platelet function by cytochalasin D. After r-tPA-evoked fibrinolysis (CLI45: median 78%; 72/85.5, 25th/75th percentile), FXIII (90%; 82.5/96, P = 0.025), PCC (89%; 74/91, P = 0.0465), and TA (94%; 92/96, P = 0.001) but not rFVIIa (79%; 72/86.5, P = 1.0) significantly attenuated the decrease in CLI. Similarly, CLI60 increased only with FXIII (66%; 33/90.5, P = 0.017) and TA (90%; 89/92, P = 0.001) compared with r-tPA alone (21%; 7/59). After abolition of platelet function by cytochalasin D, only TA (95%; 89/97.5, P = 0.0025) and PCC (84%; 70.5/90, P = 0.0305) but not FXIII or rFVIIa significantly increased CLI45 and CLI60 (TA: 89%; 84.5/96, P = 0.01 and PCC: 55%; 29.5/60, P = 0.0405) compared with r-tPA alone (CLI45: 59%; 40.5/72.5 and CLI60: 10%; 0/30). In thromboelastometric assays using whole blood, only TA, FXIII, and PCC significantly

  5. Significant Growth Inhibition of Canine Mammary Carcinoma Xenografts following Treatment with Oncolytic Vaccinia Virus GLV-1h68

    Science.gov (United States)

    Gentschev, Ivaylo; Ehrig, Klaas; Donat, Ulrike; Hess, Michael; Rudolph, Stephan; Chen, Nanhai; Yu, Yong A.; Zhang, Qian; Bullerdiek, Jörn; Nolte, Ingo; Stritzker, Jochen; Szalay, Aladar A.

    2010-01-01

    Canine mammary carcinoma is a highly metastatic tumor that is poorly responsive to available treatment. Therefore, there is an urgent need to identify novel agents for therapy of this disease. Recently, we reported that the oncolytic vaccinia virus GLV-1h68 could be a useful tool for therapy of canine mammary adenoma in vivo. In this study we analyzed the therapeutic effect of GLV-1h68 against canine mammary carcinoma. Cell culture data demonstrated that GLV-1h68 efficiently infected and destroyed cells of the mammary carcinoma cell line MTH52c. Furthermore, after systemic administration, this attenuated vaccinia virus strain primarily replicated in canine tumor xenografts in nude mice. Finally, infection with GLV-1h68 led to strong inflammatory and oncolytic effects resulting in significant growth inhibition of the tumors. In summary, the data showed that the GLV-1h68 virus strain has promising potential for effective treatment of canine mammary carcinoma. PMID:20631910

  6. PET imaging of oncolytic VSV expressing the mutant HSV-1 thymidine kinase transgene in a preclinical HCC rat model.

    Science.gov (United States)

    Muñoz-Álvarez, Kim A; Altomonte, Jennifer; Laitinen, Iina; Ziegler, Sibylle; Steiger, Katja; Esposito, Irene; Schmid, Roland M; Ebert, Oliver

    2015-04-01

    Hepatocellular carcinoma (HCC) is the most predominant form of liver cancer and the third leading cause of cancer-related death worldwide. Due to the relative ineffectiveness of conventional HCC therapies, oncolytic viruses have emerged as novel alternative treatment agents. Our previous studies have demonstrated significant prolongation of survival in advanced HCC in rats after oncolytic vesicular stomatitis virus (VSV) treatment. In this study, we aimed to establish a reporter system to reliably and sensitively image VSV in a clinically relevant model of HCC for clinical translation. To this end, an orthotopic, unifocal HCC model in immune-competent Buffalo rats was employed to test a recombinant VSV vector encoding for an enhanced version of the herpes simplex virus 1 (HSV-1) thymidine kinase (sr39tk) reporter, which would allow the indirect detection of VSV via positron emission tomography (PET). The resulting data revealed specific tracer uptake in VSV-HSV1-sr39tk-treated tumors. Further characterization of the VSV-HSV1-sr39tk vector demonstrated its optimal detection time-point after application and its detection limit via PET. In conclusion, oncolytic VSV expressing the HSV1-sr39tk reporter gene allows for highly sensitive in vivo imaging via PET. Therefore, this imaging system may be directly translatable and beneficial in further clinical applications.

  7. Oncolytic virotherapy for pediatric malignancies: future prospects

    Directory of Open Access Journals (Sweden)

    Waters AM

    2016-08-01

    Full Text Available Alicia M Waters,1 Gregory K Friedman,2 Eric K Ring,2 Elizabeth A Beierle1 1Department of Surgery, School of Medicine, University of Alabama at Birmingham, Birmingham, AL, USA; 2Department of Pediatrics, Division of Hematology-Oncology, School of Medicine, University of Alabama at Birmingham, Birmingham, AL, USA Abstract: Pediatric solid tumors remain a major health concern, with nearly 16,000 children diagnosed each year. Of those, ~2,000 succumb to their disease, and survivors often suffer from lifelong disability secondary to toxic effects of current treatments. Countless multimodality ­treatment regimens are being explored to make advances against this deadly disease. One targeted treatment approach is oncolytic virotherapy. Conditionally replicating viruses can infect tumor cells while leaving normal cells unharmed. Four viruses have been advanced to pediatric clinical trials, including herpes simplex virus-1, Seneca Valley virus, reovirus, and vaccinia virus. In this review, we discuss the mechanism of action of each virus, pediatric preclinical studies conducted to date, past and ongoing pediatric clinical trials, and potential future direction for these novel viral therapeutics. Keywords: oncolytic virus, herpes simplex virus, Seneca Valley virus, reovirus, vaccinia

  8. Oncolytic Bluetongue Viruses: Promise, Progress, and Perspectives

    Science.gov (United States)

    Li, Joseph K.-K.

    2011-01-01

    Humans are sero-negative toward bluetongue viruses (BTVs) since BTVs do not infect normal human cells. Infection and selective degradation of several human cancer cell lines but not normal ones by five US BTV serotypes have been investigated. We determined the susceptibilities of many normal and human cancer cells to BTV infections and made comparative kinetic analyses of their cytopathic effects, survival rates, ultra-structural changes, cellular apoptosis and necrosis, cell cycle arrest, cytokine profiles, viral genome, mRNAs, and progeny titers. The wild-type US BTVs, without any genetic modifications, could preferentially infect and degrade several types of human cancer cells but not normal cells. Their selective and preferential BTV-degradation of human cancer cells is viral dose–dependent, leading to effective viral replication, and induced apoptosis. Xenograft tumors in mice were substantially reduced by a single intratumoral BTV injection in initial in vivo experiments. Thus, wild-type BTVs, without genetic modifications, have oncolytic potentials. They represent an attractive, next generation of oncolytic viral approach for potential human cancer therapy combined with current anti-cancer agents and irradiation. PMID:21747785

  9. Rapid Generation of Multiple Loci-Engineered Marker-free Poxvirus and Characterization of a Clinical-Grade Oncolytic Vaccinia Virus

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    Zong Sheng Guo

    2017-12-01

    Full Text Available Recombinant poxviruses, utilized as vaccine vectors and oncolytic viruses, often require manipulation at multiple genetic loci in the viral genome. It is essential for viral vectors to possess no adventitious mutations and no (antibiotic selection marker in the final product for human patients in order to comply with the guidance from the regulatory agencies. Rintoul et al. have previously developed a selectable and excisable marker (SEM system for the rapid generation of recombinant vaccinia virus. In the current study, we describe an improved methodology for rapid creation and selection of recombinant poxviruses with multiple genetic manipulations solely based on expression of a fluorescent protein and with no requirement for drug selection that can lead to cellular stress and the risk of adventitious mutations throughout the viral genome. Using this improved procedure combined with the SEM system, we have constructed multiple marker-free oncolytic poxviruses expressing different cytokines and other therapeutic genes. The high fidelity of inserted DNA sequences validates the utility of this improved procedure for generation of therapeutic viruses for human patients. We have created an oncolytic poxvirus expressing human chemokine CCL5, designated as vvDD-A34R-hCCL5, with manipulations at two genetic loci in a single virus. Finally, we have produced and purified this virus in clinical grade for its use in a phase I clinical trial and presented data on initial in vitro characterization of the virus.

  10. Genetic and phenotypic properties of vero cell-adapted Japanese encephalitis virus SA14-14-2 vaccine strain variants and a recombinant clone, which demonstrates attenuation and immunogenicity in mice.

    Science.gov (United States)

    Gromowski, Gregory D; Firestone, Cai-Yen; Bustos-Arriaga, José; Whitehead, Stephen S

    2015-01-01

    The live-attenuated Japanese encephalitis virus (JEV) SA14-14-2 vaccine, produced in primary hamster kidney cells, is safe and effective. Past attempts to adapt this virus to replicate in cells that are more favorable for vaccine production resulted in mutations that significantly reduced immunogenicity. In this study, 10 genetically distinct Vero cell-adapted JEV SA14-14-2 variants were isolated and a recombinant wild-type JEV clone, modified to contain the JEV SA14-14-2 polyprotein amino acid sequence, was recovered in Vero cells. A single capsid protein mutation (S66L) was important for Vero cell-adaptation. Mutations were also identified that modulated virus sensitivity to type I interferon-stimulation in Vero cells. A subset of JEV SA14-14-2 variants and the recombinant clone were evaluated in vivo and exhibited levels of attenuation that varied significantly in suckling mice, but were avirulent and highly immunogenic in weanling mice and are promising candidates for the development of a second-generation, recombinant vaccine. © The American Society of Tropical Medicine and Hygiene.

  11. Recombinant human erythropoietin pretreatment attenuates acute renal tubular injury against ischemia-reperfusion by restoring transient receptor potential channel-6 expression and function in collecting ducts.

    Science.gov (United States)

    Shen, Sai'e; Jin, Yi; Li, Weiyan; Liu, Xiaoming; Zhang, Tingting; Xia, Weiliang; Wang, Yingwei; Ma, Ke

    2014-10-01

    Acute renal tubular injury is a serious complication in the postoperative period, which is associated with high mortality and increased ICU stay. We aimed to demonstrate the protective effect of rhEPO against acute tubular injury induced by ischemia-reperfusion and to explore the mechanism of canonical transient receptor potential channel-6. Randomized laboratory animal study. Animal research laboratory. Male Sprague-Dawley rats were randomly divided into three groups: the sham group, the control group, and the rhEPO group. Experimental acute tubular injury was established in rats by bilateral renal arterial occlusion for 30 minutes followed by reperfusion. Blood samples were obtained for cystatin-C and neutrophil gelatinase-associated lipocalin measurements by enzyme-linked immunosorbance assays. Seventy-two hours after reperfusion, urine samples were collected for osmolality and fractional excretion of sodium (%) assays on a chemistry analyzer. Kidneys were harvested at 24, 48, and 72 hours after reperfusion. Transient receptor potential channel-6, aquaporin-2, and Na,K-ATPase expression in collecting ducts were studied by immunofluorescence and Western blot. Coimmunoprecipitations were also performed to identify the possible signalplex relation between transient receptor potential channel-6 and aquaporin-2 or Na,K-ATPase channels. RhEPO pretreatment significantly inhibited serum cystatin-C (2 hr: 453 ± 64 μg/L vs 337 ± 28 μg/L, p human erythropoietin greatly improved the ischemia-reperfusion-induced attenuation of transient receptor potential channel-6 expression (48 hr: 42% ± 2% vs 67% ± 2% and 72 hr: 55% ± 2% vs 66% ± 2%), as well as aquaporin-2 and Na,K-ATPase expression in collecting ducts. Transient receptor potential channel-6 functionally interacted with Na,K-ATPase but not aquaporin-2. Recombinant human erythropoietin pretreatment at the dose of 5,000 IU/kg potently prevented ischemia-reperfusion-induced acute tubular injury, which might be

  12. Recombinant mumps virus as a cancer therapeutic agent

    Directory of Open Access Journals (Sweden)

    Arun Ammayappan

    2016-01-01

    Full Text Available Mumps virus belongs to the family of Paramyxoviridae and has the potential to be an oncolytic agent. Mumps virus Urabe strain had been tested in the clinical setting as a treatment for human cancer four decades ago in Japan. These clinical studies demonstrated that mumps virus could be a promising cancer therapeutic agent that showed significant antitumor activity against various types of cancers. Since oncolytic virotherapy was not in the limelight until the beginning of the 21st century, the interest to pursue mumps virus for cancer treatment slowly faded away. Recent success stories of oncolytic clinical trials prompted us to resurrect the mumps virus and to explore its potential for cancer treatment. We have obtained the Urabe strain of mumps virus from Osaka University, Japan, which was used in the earlier human clinical trials. In this report we describe the development of a reverse genetics system from a major isolate of this Urabe strain mumps virus stock, and the construction and characterization of several recombinant mumps viruses with additional transgenes. We present initial data demonstrating these recombinant mumps viruses have oncolytic activity against tumor cell lines in vitro and some efficacy in preliminary pilot animal tumor models.

  13. Recombinant mumps virus as a cancer therapeutic agent.

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    Ammayappan, Arun; Russell, Stephen J; Federspiel, Mark J

    2016-01-01

    Mumps virus belongs to the family of Paramyxoviridae and has the potential to be an oncolytic agent. Mumps virus Urabe strain had been tested in the clinical setting as a treatment for human cancer four decades ago in Japan. These clinical studies demonstrated that mumps virus could be a promising cancer therapeutic agent that showed significant antitumor activity against various types of cancers. Since oncolytic virotherapy was not in the limelight until the beginning of the 21(st) century, the interest to pursue mumps virus for cancer treatment slowly faded away. Recent success stories of oncolytic clinical trials prompted us to resurrect the mumps virus and to explore its potential for cancer treatment. We have obtained the Urabe strain of mumps virus from Osaka University, Japan, which was used in the earlier human clinical trials. In this report we describe the development of a reverse genetics system from a major isolate of this Urabe strain mumps virus stock, and the construction and characterization of several recombinant mumps viruses with additional transgenes. We present initial data demonstrating these recombinant mumps viruses have oncolytic activity against tumor cell lines in vitro and some efficacy in preliminary pilot animal tumor models.

  14. The Long-Term Safety, Public Health Impact, and Cost-Effectiveness of Routine Vaccination with a Recombinant, Live-Attenuated Dengue Vaccine (Dengvaxia: A Model Comparison Study.

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    Stefan Flasche

    2016-11-01

    Full Text Available Large Phase III trials across Asia and Latin America have recently demonstrated the efficacy of a recombinant, live-attenuated dengue vaccine (Dengvaxia over the first 25 mo following vaccination. Subsequent data collected in the longer-term follow-up phase, however, have raised concerns about a potential increase in hospitalization risk of subsequent dengue infections, in particular among young, dengue-naïve vaccinees. We here report predictions from eight independent modelling groups on the long-term safety, public health impact, and cost-effectiveness of routine vaccination with Dengvaxia in a range of transmission settings, as characterised by seroprevalence levels among 9-y-olds (SP9. These predictions were conducted for the World Health Organization to inform their recommendations on optimal use of this vaccine.The models adopted, with small variations, a parsimonious vaccine mode of action that was able to reproduce quantitative features of the observed trial data. The adopted mode of action assumed that vaccination, similarly to natural infection, induces transient, heterologous protection and, further, establishes a long-lasting immunogenic memory, which determines disease severity of subsequent infections. The default vaccination policy considered was routine vaccination of 9-y-old children in a three-dose schedule at 80% coverage. The outcomes examined were the impact of vaccination on infections, symptomatic dengue, hospitalised dengue, deaths, and cost-effectiveness over a 30-y postvaccination period. Case definitions were chosen in accordance with the Phase III trials. All models predicted that in settings with moderate to high dengue endemicity (SP9 ≥ 50%, the default vaccination policy would reduce the burden of dengue disease for the population by 6%-25% (all simulations: -3%-34% and in high-transmission settings (SP9 ≥ 70% by 13%-25% (all simulations: 10%- 34%. These endemicity levels are representative of the

  15. Recombinant Newcastle disease virus expressing IL15 demonstrates promising antitumor efficiency in melanoma model

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    Recombinant Newcastle Disease Virus (rNDV) has shown oncolytic therapeutic effect in preclinical studies. Previous data indicate that rNDV carrying IL2 has shown promise in cancer therapy. Due to the significant side effects of IL2, IL15 has been introduced into cancer therapy. A number of studies h...

  16. Oncolytic Seneca Valley Virus: past perspectives and future directions

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    Burke MJ

    2016-09-01

    Full Text Available Michael J Burke Department of Pediatrics, Division of Pediatric Oncology, Medical College of Wisconsin, MACC Fund Research Center, Milwaukee, WI, USA Abstract: Seneca Valley Virus isolate 001 (SVV-001 is an oncolytic RNA virus of the Picornaviridae family. It is also the first picornavirus discovered of the novel genus Senecavirus. SVV-001 replicates through an RNA intermediate, bypassing a DNA phase, and is unable to integrate into the host genome. SVV-001 was originally discovered as a contaminant in the cell culture of fetal retinoblasts and has since been identified as a potent oncolytic virus against tumors of neuroendocrine origin. SVV-001 has a number of features that make it an attractive oncolytic virus, namely, its ability to target and penetrate solid tumors via intravenous administration, inability for insertional mutagenesis, and being a self-replicating RNA virus with selective tropism for cancer cells. SVV-001 has been studied in both pediatric and adult early phase studies reporting safety and some clinical efficacy, albeit primarily in adult tumors. This review summarizes the current knowledge of SVV-001 and what its future as an oncolytic virus may hold. Keywords: oncolytic, virus, oncology, Seneca, valley

  17. Therapeutic oncolytic viruses: clinical advances and future directions.

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    Warner, Susanne G; O'Leary, Michael P; Fong, Yuman

    2017-09-01

    The present review will highlight recent advances in the clinical application of oncolytic viral therapy. Until recently, oncolytic viral researchers saw the immune system as an enemy that would clear the virus from the bloodstream. However, researchers now understand that sustained responses are seen in those patients with more robust antitumor immune responses. Much of the current focus in oncolytic viral research is trained on manipulation of the immune system to affect cancer cell killing in the tumor microenvironment and to facilitate durable systemic antitumor immunity. Many investigators have demonstrated synergistic effects of checkpoint inhibition and other immune therapies with viral administration. At the same time, insertion of various markers enables noninvasive deep tissue imaging. Finally, following regulatory approval in the United States and Europe, unbridled clinical use of T-VEC for patients with metastatic melanoma is also generating large volumes of patient data that will help elucidate strengths and weaknesses of oncolytic viral therapy. Perhaps the most telling sign of the field's future is a seismic shift in clinical trials with more investigators combining virus and immunotherapies. This article reviews the current state of therapeutic oncolytic viruses in clinical use, and explores future directions of the field.

  18. Targeting pediatric cancer stem cells with oncolytic virotherapy.

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    Friedman, Gregory K; Cassady, Kevin A; Beierle, Elizabeth A; Markert, James M; Gillespie, G Yancey

    2012-04-01

    Cancer stem cells (CSCs), also termed "cancer-initiating cells" or "cancer progenitor cells," which have the ability to self-renew, proliferate, and maintain the neoplastic clone, have recently been discovered in a wide variety of pediatric tumors. These CSCs are thought to be responsible for tumorigenesis and tumor maintenance, aggressiveness, and recurrence due to inherent resistance to current treatment modalities such as chemotherapy and radiation. Oncolytic virotherapy offers a novel, targeted approach for eradicating pediatric CSCs using mechanisms of cell killing that differ from conventional therapies. Moreover, oncolytic viruses have the ability to target specific features of CSCs such as cell-surface proteins, transcription factors, and the CSC microenvironment. Through genetic engineering, a wide variety of foreign genes may be expressed by oncolytic viruses to augment the oncolytic effect. We review the current data regarding the ability of several types of oncolytic viruses (herpes simplex virus-1, adenovirus, reovirus, Seneca Valley virus, vaccinia virus, Newcastle disease virus, myxoma virus, vesicular stomatitis virus) to target and kill both CSCs and tumor cells in pediatric tumors. We highlight advantages and limitations of each virus and potential ways in which next-generation engineered viruses may target resilient CSCs.

  19. Safety profile of the viral vectors of attenuated fowlpox strain FP9 and modified vaccinia virus Ankara recombinant for either of 2 preerythrocytic malaria antigens, ME-TRAP or the circumsporozoite protein, in children and adults in Kenya.

    Science.gov (United States)

    Bejon, Philip; Peshu, Norbert; Gilbert, Sarah C; Lowe, Brett S; Molyneux, Catherine S; Forsdyke, John; Lang, Trudie; Hill, Adrian V S; Marsh, Kevin

    2006-04-15

    We are developing a heterologous prime-boost vaccine strategy against malaria. This approach uses sequential immunization with different vectors to deliver a common preerythrocytic malaria antigen. Preliminary evidence of efficacy and safety has been previously documented in studies from an area where malaria is nonendemic. Additional safety data from an area where malaria is endemic are now required before larger-scale studies are undertaken to determine the efficacy of this vaccine strategy in the field. Other modified vaccinia virus Ankara (MVA) recombinants and prime-boost immunizations are being developed as vaccines against human immunodeficiency virus (HIV) infection, tuberculosis, and cancer, and MVA is a candidate attenuated smallpox vaccine. Candidate vaccines against malaria were intradermally administered to 73 adults (7 of whom were HIV positive) and 22 children in Kenya. These vaccines used the attenuated fowlpox strain FP9 and the MVA recombinant for either of 2 preerythrocytic malaria antigens, multiple preerythrocytic-stage epitopes joined with the preerythrocytic-stage antigen TRAP (ME-TRAP) and the circumsporozoite protein (CS). Adverse events were recorded. Reactogenicity was mild. MVA caused less frequent and less severe cutaneous reaction if given after FP9 priming. Half doses reduced the frequency and the severity of systemic reactogenicity, and particular vaccine lots were associated with different reactogenicities. Unexpectedly, prior immunity to the ME-TRAP antigen appeared to be protective against local reactions after immunization. Where the final intention is to use MVA after FP9 priming, previous testing of MVA alone overestimates reactogenicity. These recombinant vectors appear to be safe and suitable for use in larger-scale studies of children in Africa and of HIV-positive individuals.

  20. Vesicular Stomatitis Virus Has Extensive Oncolytic Activity against Human Sarcomas: Rare Resistance Is Overcome by Blocking Interferon Pathways ▿

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    Paglino, Justin C.; van den Pol, Anthony N.

    2011-01-01

    Oncolytic viruses have been tested against many carcinomas of ectodermal and endodermal origin; however, sarcomas, arising from mesoderm, have received relatively little attention. Using 13 human sarcomas representing seven tumor types, we assessed the efficiency of infection, cytolysis, and replication of green fluorescent protein (GFP)-expressing vesicular stomatitis virus (VSV) and its oncolytically enhanced mutant VSV-rp30a. Both viruses efficiently infected and killed 12 of 13 sarcomas. VSV-rp30a showed a faster rate of infection and replication. In vitro and in vivo, VSV was selective for sarcomas compared with normal mesoderm. A single intravenous injection of VSV-rp30a selectively infected all subcutaneous human sarcomas tested in mice and arrested the growth of tumors that otherwise grew 11-fold. In contrast to other sarcomas, synovial sarcoma SW982 demonstrated remarkable resistance, even to high titers of virus (multiplicity of infection [MOI] of 100). We found no dysfunction in VSV binding or internalization. SW982 also resisted infection by human cytomegalovirus and Sindbis virus, suggesting a virus resistance mechanism based on an altered antiviral state. Quantitative reverse transcriptase (qRT)-PCR analysis revealed a heightened basal expression of interferon-stimulated genes (ISGs). Pretreatment, but not cotreatment, with interferon attenuators valproate, Jak1 inhibitor, or vaccinia virus B18R protein rendered SW982 highly susceptible, and this correlated with downregulation of ISG expression. Jak1 inhibitor pretreatment also enhanced susceptibility in moderately VSV-resistant liposarcoma and bladder carcinoma. Overall, we find that the potential efficacy of VSV as an oncolytic agent extends to nonhematologic mesodermal tumors and that unusually strong resistance to VSV oncolysis can be overcome with interferon attenuators. PMID:21734048

  1. Immune Suppression during Oncolytic Virotherapy for High-Grade Glioma; Yes or No?

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    Koks, Carolien A E; De Vleeschouwer, Steven; Graf, Norbert; Van Gool, Stefaan W

    2015-01-01

    Oncolytic viruses have been seriously considered for glioma therapy over the last 20 years. The oncolytic activity of several oncolytic strains has been demonstrated against human glioma cell lines and in in vivo xenotransplant models. So far, four of these stains have additionally completed the first phase I/II trials in relapsed glioma patients. Though safety and feasibility have been demonstrated, therapeutic efficacy in these initial trials, when described, was only minor. The role of the immune system in oncolytic virotherapy for glioma remained much less studied until recent years. When investigated, the immune system, adept at controlling viral infections, is often hypothesized to be a strong hurdle to successful oncolytic virotherapy. Several preclinical studies have therefore aimed to improve oncolytic virotherapy efficacy by combining it with immune suppression or evasion strategies. More recently however, a new paradigm has developed in the oncolytic virotherapy field stating that oncolytic virus-mediated tumor cell death can be accompanied by elicitation of potent activation of innate and adaptive anti-tumor immunity that greatly improves the efficacy of certain oncolytic strains. Therefore, it seems the three-way interaction between oncolytic virus, tumor and immune system is critical to the outcome of antitumor therapy. In this review we discuss the studies which have investigated how the immune system and oncolytic viruses interact in models of glioma. The novel insights generated here hold important implications for future research and should be incorporated into the design of novel clinical trials.

  2. Oncolytic Sendai virus-based virotherapy for cancer: recent advances

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    Saga, Kotaro; Kaneda, Yasufumi

    2015-01-01

    Many drugs have been developed and optimized for the treatment of cancer; however, it is difficult to completely cure cancer with anticancer drugs alone. Therefore, the development of new therapeutic technologies, in addition to new anticancer drugs, is necessary for more effective oncotherapy. Oncolytic viruses are one potential new anticancer strategy. Various oncolytic viruses have been developed for safe and effective oncotherapy. Recently, Sendai virus-based oncotherapy has been reported by several groups, and attention has been drawn to its unique anticancer mechanisms, which are different from those of the conventional oncolytic viruses that kill cancer cells by cancer cell-selective replication. Here, we introduce Sendai virus-based virotherapy and its anticancer mechanisms. PMID:27512677

  3. Oncolytic Sendai virus-based virotherapy for cancer: recent advances

    Directory of Open Access Journals (Sweden)

    Saga K

    2015-10-01

    Full Text Available Kotaro Saga, Yasufumi Kaneda Division of Gene Therapy Science, Graduate School of Medicine, Osaka University, Osaka, Japan Abstract: Many drugs have been developed and optimized for the treatment of cancer; however, it is difficult to completely cure cancer with anticancer drugs alone. Therefore, the development of new therapeutic technologies, in addition to new anticancer drugs, is necessary for more effective oncotherapy. Oncolytic viruses are one potential new anticancer strategy. Various oncolytic viruses have been developed for safe and effective oncotherapy. Recently, Sendai virus-based oncotherapy has been reported by several groups, and attention has been drawn to its unique anticancer mechanisms, which are different from those of the conventional oncolytic viruses that kill cancer cells by cancer cell-selective replication. Here, we introduce Sendai virus-based virotherapy and its anticancer mechanisms. Keywords: HVJ-E, cancer therapy, apoptosis, necroptosis, anticancer immunity 

  4. Combining HDAC inhibitors with oncolytic virotherapy for cancer therapy

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    Nakashima H

    2015-11-01

    Full Text Available Hiroshi Nakashima, Tran Nguyen, Ennio Antonio ChioccaDepartment of Neurosurgery, Brigham and Women's Hospital, Boston, MA, USAAbstract: Histone deacetylase (HDAC enzymes play a critical role in the epigenetic regulation of cellular functions and signaling pathways in many cancers. HDAC inhibitors (HDACi have been validated for single use or in combination with other drugs in oncologic therapeutics. An even more novel combination therapy with HDACi is to use them with an oncolytic virus. HDACi may lead to an amplification of tumor-specific lytic effects by facilitating increased cycles of viral replication, but there may also be direct anticancer effects of the drug by itself. Here, we review the molecular mechanisms of anti-cancer effects of the combination of oncolytic viruses with HDACi.Keywords: epigenetics, glioma, oncolytic virus, HDAC inhibitor, HSV-1, cancer

  5. Tumor-Associated Macrophages in Oncolytic Virotherapy: Friend or Foe?

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    Nicholas L. Denton

    2016-07-01

    Full Text Available Cancer therapy remains a challenge due to toxicity limitations of chemotherapy and radiation therapy. Oncolytic viruses that selectively replicate and destroy cancer cells are of increasing interest. In addition to direct cell lysis, these vectors stimulate an anti-tumor immune response. A key regulator of tumor immunity is the tumor-associated macrophage population. Macrophages can either support oncolytic virus therapy through pro-inflammatory stimulation of the anti-tumor response at the cost of hindering direct oncolysis or through immunosuppressive protection of virus replication at the cost of hindering the anti-tumor immune response. Despite similarities in macrophage interaction between adult and pediatric tumors and the abundance of research supporting macrophage modulation in adult tumors, there are few studies investigating macrophage modulation in pediatric cancers or modulation of immunotherapy. We review the current state of knowledge regarding macrophages in cancers and their influence on oncolytic virotherapy.

  6. Oncolytic Viruses: Therapeutics With an Identity Crisis.

    Science.gov (United States)

    Breitbach, Caroline J; Lichty, Brian D; Bell, John C

    2016-07-01

    Oncolytic viruses (OV) are replicating viral therapeutics for the treatment of cancer and have been in laboratory development for about twenty years. Recently, the FDA approved Imlygic, a herpes virus based therapeutic for the treatment of melanoma and thus OVs have entered a new era where they are a weapon in the armament of the oncologist. OVs are unique therapeutics with multiple mechanisms of therapeutic activity. The exact path for their development and eventual uptake by pharmaceutical companies is somewhat clouded by an uncertain identity. Are they vaccines, tumour lysing therapeutics, inducers of innate immunity, gene therapy vectors, anti-vascular agents or all of the above? Should they be developed as stand-alone loco-regional therapeutics, systemically delivered tumour hunters or immune modulators best tested as combination therapeutics? We summarize data here supporting the idea, depending upon the virus, that OVs can be any or all of these things. Pursuing a "one-size fits all" approach is counter-productive to their clinical development and instead as a field we should build on the strengths of individual virus platforms. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

  7. Oncolytic Viruses: Therapeutics With an Identity Crisis

    Directory of Open Access Journals (Sweden)

    Caroline J. Breitbach

    2016-07-01

    Full Text Available Oncolytic viruses (OV are replicating viral therapeutics for the treatment of cancer and have been in laboratory development for about twenty years. Recently, the FDA approved Imlygic, a herpes virus based therapeutic for the treatment of melanoma and thus OVs have entered a new era where they are a weapon in the armament of the oncologist. OVs are unique therapeutics with multiple mechanisms of therapeutic activity. The exact path for their development and eventual uptake by pharmaceutical companies is somewhat clouded by an uncertain identity. Are they vaccines, tumour lysing therapeutics, inducers of innate immunity, gene therapy vectors, anti-vascular agents or all of the above? Should they be developed as stand-alone loco-regional therapeutics, systemically delivered tumour hunters or immune modulators best tested as combination therapeutics? We summarize data here supporting the idea, depending upon the virus, that OVs can be any or all of these things. Pursuing a “one-size fits all” approach is counter-productive to their clinical development and instead as a field we should build on the strengths of individual virus platforms.

  8. Arming oncolytic viruses to leverage antitumor immunity.

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    de Gruijl, Tanja D; Janssen, Axel B; van Beusechem, Victor W

    2015-07-01

    Over the past decade, the cytolytic capabilities of oncolytic viruses (OVs), exploited to selectively eliminate neoplastic cells, have become secondary to their use to elicit a tumor-directed immune response. Here, based on an NCBI-PubMed literature survey, we review the efforts undertaken to arm OVs in order to improve therapeutic antitumor responses upon administration of these agents. Specifically, we explore the different options to modulate immune suppression in the tumor microenvironment (TME) and to facilitate the generation of effective antitumor responses that have been investigated in conjunction with OVs in recent years. Their induction of immunogenic tumor cell death and association with pro-inflammatory signals make OVs attractive immunotherapeutic modalities. The first promising clinical results with immunologically armed OVs warrant their further optimization and development. OVs should be modified to avoid detrimental effects of pre-existent anti-OV immunity as well as for increased tumor targeting and selectivity, so as to ultimately allow for systemic administration while achieving local immune potentiation and tumor elimination in the TME. In particular, a combination of trans-genes encoding bispecific T-cell engagers, immune checkpoint blockers and antigen-presenting cell enhancers will remove suppressive hurdles in the TME and allow for optimal antitumor efficacy of armed OVs.

  9. Experimental therapies: gene therapies and oncolytic viruses.

    Science.gov (United States)

    Hulou, M Maher; Cho, Choi-Fong; Chiocca, E Antonio; Bjerkvig, Rolf

    2016-01-01

    Glioblastoma is the most common and aggressive primary brain tumor in adults. Over the past three decades, the overall survival time has only improved by a few months, therefore novel alternative treatment modalities are needed to improve clinical management strategies. Such strategies should ultimately extend patient survival. At present, the extensive insight into the molecular biology of gliomas, as well as into genetic engineering techniques, has led to better decision processes when it comes to modifying the genome to accommodate suicide genes, cytokine genes, and tumor suppressor genes that may kill cancer cells, and boost the host defensive immune system against neoantigenic cytoplasmic and nuclear targets. Both nonreplicative viral vectors and replicating oncolytic viruses have been developed for brain cancer treatment. Stem cells, microRNAs, nanoparticles, and viruses have also been designed. These have been armed with transgenes or peptides, and have been used both in laboratory-based experiments as well as in clinical trials, with the aim of improving selective killing of malignant glioma cells while sparing normal brain tissue. This chapter reviews the current status of gene therapies for malignant gliomas and highlights the most promising viral and cell-based strategies under development. © 2016 Elsevier B.V. All rights reserved.

  10. Retargeting of Viruses to Generate Oncolytic Agents

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    M. H. Verheije

    2012-01-01

    Full Text Available Oncolytic virus therapy is based on the ability of viruses to effectively infect and kill tumor cells without destroying the normal tissues. While some viruses seem to have a natural preference for tumor cells, most viruses require the modification of their tropism to specifically enter and replicate in such cells. This review aims to describe the transductional targeting strategies currently employed to specifically redirect viruses towards surface receptors on tumor cells. Three major strategies can be distinguished; they involve (i the incorporation of new targeting specificity into a viral surface protein, (ii the incorporation of a scaffold into a viral surface protein to allow the attachment of targeting moieties, and (iii the use of bispecific adapters to mediate targeting of a virus to a specified moiety on a tumor cell. Of each strategy key features, advantages and limitations are discussed and examples are given. Because of their potential to cause sustained, multiround infection—a desirable characteristic for eradicating tumors—particular attention is given to viruses engineered to become self-targeted by the genomic expression of a bispecific adapter protein.

  11. Resistance of pancreatic cancer cells to oncolytic vesicular stomatitis virus: role of type I interferon signaling.

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    Moerdyk-Schauwecker, Megan; Shah, Nirav R; Murphy, Andrea M; Hastie, Eric; Mukherjee, Pinku; Grdzelishvili, Valery Z

    2013-02-05

    Oncolytic virus (OV) therapy takes advantage of common cancer characteristics, such as defective type I interferon (IFN) signaling, to preferentially infect and kill cancer cells with viruses. Our recent study (Murphy et al., 2012. J. Virol. 86, 3073-87) found human pancreatic ductal adenocarcinoma (PDA) cells were highly heterogeneous in their permissiveness to vesicular stomatitis virus (VSV) and suggested at least some resistant cell lines retained functional type I IFN responses. Here we examine cellular responses to infection by the oncolytic VSV recombinant VSV-ΔM51-GFP by analyzing a panel of 11 human PDA cell lines for expression of 33 genes associated with type I IFN pathways. Although all cell lines sensed infection by VSV-ΔM51-GFP and most activated IFN-α and β expression, only resistant cell lines displayed constitutive high-level expression of the IFN-stimulated antiviral genes MxA and OAS. Inhibition of JAK/STAT signaling decreased levels of MxA and OAS and increased VSV infection, replication and oncolysis, further implicating IFN responses in resistance. Unlike VSV, vaccinia and herpes simplex virus infectivity and killing of PDA cells was independent of the type I IFN signaling profile, possibly because these two viruses are better equipped to evade type I IFN responses. Our study demonstrates heterogeneity in the type I IFN signaling status of PDA cells and suggests MxA and OAS as potential biomarkers for PDA resistance to VSV and other OVs sensitive to type I IFN responses. Copyright © 2012 Elsevier Inc. All rights reserved.

  12. Big Data Offers Novel Insights for Oncolytic Virus Immunotherapy

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    Stephanie L. Swift

    2016-02-01

    Full Text Available Large-scale assays, such as microarrays, next-generation sequencing and various “omics” technologies, have explored multiple aspects of the immune response following virus infection, often from a public health perspective. Yet a lack of similar data exists for monitoring immune engagement during oncolytic virus immunotherapy (OVIT in the cancer setting. Tracking immune signatures at the tumour site can create a snapshot or longitudinally analyse immune cell activation, infiltration and functionality within global populations or individual cells. Mapping immune changes over the course of oncolytic biotherapy—from initial infection to tumour stabilisation/regression through to long-term cure or escape/relapse—has the potential to generate important therapeutic insights around virus-host interactions. Further, correlating such immune signatures with specific tumour outcomes has significant value for guiding the development of novel oncolytic virus immunotherapy strategies. Here, we provide insights for OVIT from large-scale analyses of immune populations in the infection, vaccination and immunotherapy setting. We analyse several approaches to manipulating immune engagement during OVIT. We further explore immunocentric changes in the tumour tissue following immunotherapy, and compile several immune signatures of therapeutic success. Ultimately, we highlight clinically relevant large-scale approaches with the potential to strengthen future oncolytic strategies to optimally engage the immune system.

  13. Systemic Delivery of Oncolytic Viruses: Hopes and Hurdles

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    Mark S. Ferguson

    2012-01-01

    Full Text Available Despite recent advances in both surgery and chemoradiotherapy, mortality rates for advanced cancer remain high. There is a pressing need for novel therapeutic strategies; one option is systemic oncolytic viral therapy. Intravenous administration affords the opportunity to treat both the primary tumour and any metastatic deposits simultaneously. Data from clinical trials have shown that oncolytic viruses can be systemically delivered safely with limited toxicity but the results are equivocal in terms of efficacy, particularly when delivered with adjuvant chemotherapy. A key reason for this is the rapid clearance of the viruses from the circulation before they reach their targets. This phenomenon is mainly mediated through neutralising antibodies, complement activation, antiviral cytokines, and tissue-resident macrophages, as well as nonspecific uptake by other tissues such as the lung, liver and spleen, and suboptimal viral escape from the vascular compartment. A range of methods have been reported in the literature, which are designed to overcome these hurdles in preclinical models. In this paper, the potential advantages of, and obstacles to, successful systemic delivery of oncolytic viruses are discussed. The next stage of development will be the commencement of clinical trials combining these novel approaches for overcoming the barriers with systemically delivered oncolytic viruses.

  14. Immune System, Friend or Foe of Oncolytic Virotherapy?

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    Anna C. Filley

    2017-05-01

    Full Text Available Oncolytic viruses (OVs are an emerging class of targeted anticancer therapies designed to selectively infect, replicate in, and lyse malignant cells without causing harm to normal, healthy tissues. In addition to direct oncolytic activity, OVs have shown dual promise as immunotherapeutic agents. The presence of viral infection and subsequently generated immunogenic tumor cell death trigger innate and adaptive immune responses that mediate further tumor destruction. However, antiviral immune responses can intrinsically limit OV infection, spread, and overall therapeutic efficacy. Host immune system can act both as a barrier as well as a facilitator and sometimes both at the same time based on the phase of viral infection. Thus, manipulating the host immune system to minimize antiviral responses and viral clearance while still promoting immune-mediated tumor destruction remains a key challenge facing oncolytic virotherapy. Recent clinical trials have established the safety, tolerability, and efficacy of virotherapies in the treatment of a variety of malignancies. Most notably, talimogene laherparepvec (T-VEC, a genetically engineered oncolytic herpesvirus-expressing granulocyte macrophage colony stimulating factor, was recently approved for the treatment of melanoma, representing the first OV to be approved by the FDA as an anticancer therapy in the US. This review discusses OVs and their antitumor properties, their complex interactions with the immune system, synergy between virotherapy and existing cancer treatments, and emerging strategies to augment the efficacy of OVs as anticancer therapies.

  15. Immune System, Friend or Foe of Oncolytic Virotherapy?

    Science.gov (United States)

    Filley, Anna C; Dey, Mahua

    2017-01-01

    Oncolytic viruses (OVs) are an emerging class of targeted anticancer therapies designed to selectively infect, replicate in, and lyse malignant cells without causing harm to normal, healthy tissues. In addition to direct oncolytic activity, OVs have shown dual promise as immunotherapeutic agents. The presence of viral infection and subsequently generated immunogenic tumor cell death trigger innate and adaptive immune responses that mediate further tumor destruction. However, antiviral immune responses can intrinsically limit OV infection, spread, and overall therapeutic efficacy. Host immune system can act both as a barrier as well as a facilitator and sometimes both at the same time based on the phase of viral infection. Thus, manipulating the host immune system to minimize antiviral responses and viral clearance while still promoting immune-mediated tumor destruction remains a key challenge facing oncolytic virotherapy. Recent clinical trials have established the safety, tolerability, and efficacy of virotherapies in the treatment of a variety of malignancies. Most notably, talimogene laherparepvec (T-VEC), a genetically engineered oncolytic herpesvirus-expressing granulocyte macrophage colony stimulating factor, was recently approved for the treatment of melanoma, representing the first OV to be approved by the FDA as an anticancer therapy in the US. This review discusses OVs and their antitumor properties, their complex interactions with the immune system, synergy between virotherapy and existing cancer treatments, and emerging strategies to augment the efficacy of OVs as anticancer therapies.

  16. Boosting oncolytic adenovirus potency with magnetic nanoparticles and magnetic force.

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    Tresilwised, Nittaya; Pithayanukul, Pimolpan; Mykhaylyk, Olga; Holm, Per Sonne; Holzmüller, Regina; Anton, Martina; Thalhammer, Stefan; Adigüzel, Denis; Döblinger, Markus; Plank, Christian

    2010-08-02

    Oncolytic adenoviruses rank among the most promising innovative agents in cancer therapy. We examined the potential of boosting the efficacy of the oncolytic adenovirus dl520 by associating it with magnetic nanoparticles and magnetic-field-guided infection in multidrug-resistant (MDR) cancer cells in vitro and upon intratumoral injection in vivo. The virus was complexed by self-assembly with core-shell nanoparticles having a magnetite core of about 10 nm and stabilized by a shell containing 68 mass % lithium 3-[2-(perfluoroalkyl)ethylthio]propionate) and 32 mass % 25 kDa branched polyethylenimine. Optimized virus binding, sufficiently stable in 50% fetal calf serum, was found at nanoparticle-to-virus ratios of 5 fg of Fe per physical virus particle (VP) and above. As estimated from magnetophoretic mobility measurements, 3,600 to 4,500 magnetite nanocrystallites were associated per virus particle. Ultrastructural analysis by electron and atomic force microscopy showed structurally intact viruses surrounded by magnetic particles that occasionally bridged several virus particles. Viral uptake into cells at a given virus dose was enhanced 10-fold compared to nonmagnetic virus when infections were carried out under the influence of a magnetic field. Increased virus internalization resulted in a 10-fold enhancement of the oncolytic potency in terms of the dose required for killing 50% of the target cells (IC(50) value) and an enhancement of 4 orders of magnitude in virus progeny formation at equal input virus doses compared to nonmagnetic viruses. Furthermore, the full oncolytic effect developed within two days postinfection compared with six days in a nonmagnetic virus as a reference. Plotting target cell viability versus internalized virus particles for magnetic and nonmagnetic virus showed that the inherent oncolytic productivity of the virus remained unchanged upon association with magnetic nanoparticles. Hence, we conclude that the mechanism of boosting the

  17. Characterization of herpes simplex virus 1 strains as platforms for the development of oncolytic viruses against liver cancer.

    Science.gov (United States)

    Argnani, Rafaela; Marconi, Peggy; Volpi, Ilaria; Bolanos, Elixabet; Carro, Elvira; Ried, Christine; Santamaria, Enrique; Pourchet, Aldo; Epstein, Alberto L; Brocker, Thomas; Corrales, Fernando Jose; Manservigi, Roberto; Goicoechea, Ibai; Foschini, Mariagiovanna; Hernandez-Alcoceba, Ruben

    2011-11-01

    Diverse oncolytic viruses (OV) are being designed for the treatment of cancer. The characteristics of the parental virus strains may influence the properties of these agents. To characterize two herpes simplex virus 1 strains (HSV-1 17syn(+) and HFEM) as platforms for virotherapy against liver cancer. The luciferase reporter gene was introduced in the intergenic region 20 locus of both HSV-1 strains, giving rise to the Cgal-Luc and H6-Luc viruses. Their properties were studied in hepatocellular carcinoma (HCC) cells in vitro. Biodistribution was monitored by bioluminescence imaging (BLI) in athymic mice and immune-competent Balb/c mice. Immunogenicity was studied by MHC-tetramer staining, in vivo killing assays and determination of specific antibody production. Intratumoural transgene expression and oncolytic effect were studied in HuH-7 xenografts. The H6-Luc virus displayed a syncytial phenotype and showed higher cytolytic effect on some HCC cells. Upon intravenous or intrahepatic injection in mice, both viruses showed a transient transduction of the liver with rapid relocalization of bioluminescence in adrenal glands, spinal cord, uterus and ovaries. No significant differences were observed in the immunogenicity of these viruses. Local intratumoural administration caused progressive increase in transgene expression during the first 5 days and persisted for at least 2 weeks. H6-Luc achieved faster amplification of transgene expression and stronger inhibition of tumour growth than Cgal-Luc, although toxicity of these non-attenuated viruses should be reduced to obtain a therapeutic effect. The syncytial H6-Luc virus has a strong oncolytic potential on human HCC xenografts and could be the basis for potent OV. © 2011 John Wiley & Sons A/S.

  18. Insertion of the human sodium iodide symporter to facilitate deep tissue imaging does not alter oncolytic or replication capability of a novel vaccinia virus

    Directory of Open Access Journals (Sweden)

    Mittra Arjun

    2011-03-01

    Full Text Available Abstract Introduction Oncolytic viruses show promise for treating cancer. However, to assess therapeutic efficacy and potential toxicity, a noninvasive imaging modality is needed. This study aimed to determine if insertion of the human sodium iodide symporter (hNIS cDNA as a marker for non-invasive imaging of virotherapy alters the replication and oncolytic capability of a novel vaccinia virus, GLV-1h153. Methods GLV-1h153 was modified from parental vaccinia virus GLV-1h68 to carry hNIS via homologous recombination. GLV-1h153 was tested against human pancreatic cancer cell line PANC-1 for replication via viral plaque assays and flow cytometry. Expression and transportation of hNIS in infected cells was evaluated using Westernblot and immunofluorescence. Intracellular uptake of radioiodide was assessed using radiouptake assays. Viral cytotoxicity and tumor regression of treated PANC-1tumor xenografts in nude mice was also determined. Finally, tumor radiouptake in xenografts was assessed via positron emission tomography (PET utilizing carrier-free 124I radiotracer. Results GLV-1h153 infected, replicated within, and killed PANC-1 cells as efficiently as GLV-1h68. GLV-1h153 provided dose-dependent levels of hNIS expression in infected cells. Immunofluorescence detected transport of the protein to the cell membrane prior to cell lysis, enhancing hNIS-specific radiouptake (P In vivo, GLV-1h153 was as safe and effective as GLV-1h68 in regressing pancreatic cancer xenografts (P 124I-PET. Conclusion Insertion of the hNIS gene does not hinder replication or oncolytic capability of GLV-1h153, rendering this novel virus a promising new candidate for the noninvasive imaging and tracking of oncolytic viral therapy.

  19. Oncolytic Viruses in the Treatment of Bladder Cancer

    Directory of Open Access Journals (Sweden)

    Kyle G. Potts

    2012-01-01

    Full Text Available Bladder carcinoma is the second most common malignancy of the urinary tract. Up to 85% of patients with bladder cancer are diagnosed with a tumor that is limited to the bladder mucosa (Ta, T1, and CIS. These stages are commonly termed as non-muscle-invasive bladder cancer (NMIBC. Although the treatment of NMIBC has greatly improved in recent years, there is a need for additional therapies when patients fail bacillus Calmette-Guérin (BCG and chemotherapeutic agents. We propose that bladder cancer may be an ideal target for oncolytic viruses engineered to selectively replicate in and lyse tumor cells leaving normal cells unharmed. In support of this hypothesis, here we review current treatment strategies for bladder cancer and their shortcomings, as well as recent advancements in oncolytic viral therapy demonstrating encouraging safety profiles and antitumor activity.

  20. Immunostimulatory Gene Therapy Using Oncolytic Viruses as Vehicles

    Directory of Open Access Journals (Sweden)

    Angelica Loskog

    2015-11-01

    Full Text Available Immunostimulatory gene therapy has been developed during the past twenty years. The aim of immunostimulatory gene therapy is to tilt the suppressive tumor microenvironment to promote anti-tumor immunity. Hence, like a Trojan horse, the gene vehicle can carry warriors and weapons into enemy territory to combat the tumor from within. The most promising immune stimulators are those activating and sustaining Th1 responses, but even if potent effects were seen in preclinical models, many clinical trials failed to show objective responses in cancer patients. However, with new tools to control ongoing immunosuppression in cancer patients, immunostimulatory gene therapy is now emerging as an interesting option. In parallel, oncolytic viruses have been shown to be safe in patients. To prolong immune stimulation and to increase efficacy, these two fields are now merging and oncolytic viruses are armed with immunostimulatory transgenes. These novel agents are racing towards approval as established cancer immunotherapeutics.

  1. Mathematical modeling of glioma therapy using oncolytic viruses.

    Science.gov (United States)

    Camara, Baba Issa; Mokrani, Houda; Afenya, Evans K

    2013-06-01

    Diffuse infiltrative gliomas are adjudged to be the most common primary brain tumors in adults and they tend to blend in extensively in the brain micro-environment. This makes it difficult for medical practitioners to successfully plan effective treatments. In attempts to prolong the lengths of survival times for patients with malignant brain tumors, novel therapeutic alternatives such as gene therapy with oncolytic viruses are currently being explored. Based on such approaches and existing work, a spatio-temporal model that describes interaction between tumor cells and oncolytic viruses is developed. Conditions that lead to optimal therapy in minimizing cancer cell proliferation and otherwise are analytically demonstrated. Numerical simulations are conducted with the aim of showing the impact of virotherapy on proliferation or invasion of cancer cells and of estimating survival times.

  2. Immunostimulatory Gene Therapy Using Oncolytic Viruses as Vehicles.

    Science.gov (United States)

    Loskog, Angelica

    2015-11-06

    Immunostimulatory gene therapy has been developed during the past twenty years. The aim of immunostimulatory gene therapy is to tilt the suppressive tumor microenvironment to promote anti-tumor immunity. Hence, like a Trojan horse, the gene vehicle can carry warriors and weapons into enemy territory to combat the tumor from within. The most promising immune stimulators are those activating and sustaining Th1 responses, but even if potent effects were seen in preclinical models, many clinical trials failed to show objective responses in cancer patients. However, with new tools to control ongoing immunosuppression in cancer patients, immunostimulatory gene therapy is now emerging as an interesting option. In parallel, oncolytic viruses have been shown to be safe in patients. To prolong immune stimulation and to increase efficacy, these two fields are now merging and oncolytic viruses are armed with immunostimulatory transgenes. These novel agents are racing towards approval as established cancer immunotherapeutics.

  3. Antifibrotic properties of transarterial oncolytic VSV therapy for hepatocellular carcinoma in rats with thioacetamide-induced liver fibrosis.

    Science.gov (United States)

    Altomonte, Jennifer; Marozin, Sabrina; De Toni, Enrico N; Rizzani, Antonia; Esposito, Irene; Steiger, Katja; Feuchtinger, Annette; Hellerbrand, Claus; Schmid, Roland M; Ebert, Oliver

    2013-11-01

    Recombinant vesicular stomatitis virus (VSV) shows promise for the treatment of hepatocellular carcinoma (HCC), but its safety and efficacy when administered in a setting of hepatic fibrosis, which occurs in the majority of clinical cases, is unknown. We hypothesized that VSV could provide a novel benefit to the underlying fibrosis, due to its ability to replicate and cause cell death specifically in activated hepatic stellate cells. In addition to the ability of VSV to produce a significant oncolytic response in HCC-bearing rats in the background of thioacetamide-induced hepatic fibrosis without signs of hepatotoxicity, we observed a significant downgrading of fibrosis stage, a decrease in collagen content in the liver, and modulation of gene expression in favor of fibrotic regression. Together, this work suggests that VSV is not only safe and effective for the treatment of HCC with underlying fibrosis, but it could potentially be developed for clinical application as a novel antifibrotic agent.

  4. Measles to the Rescue: A Review of Oncolytic Measles Virus

    Directory of Open Access Journals (Sweden)

    Sarah Aref

    2016-10-01

    Full Text Available Oncolytic virotherapeutic agents are likely to become serious contenders in cancer treatment. The vaccine strain of measles virus is an agent with an impressive range of oncolytic activity in pre-clinical trials with increasing evidence of safety and efficacy in early clinical trials. This paramyxovirus vaccine has a proven safety record and is amenable to careful genetic modification in the laboratory. Overexpression of the measles virus (MV receptor CD46 in many tumour cells may direct the virus to preferentially enter transformed cells and there is increasing awareness of the importance of nectin-4 and signaling lymphocytic activation molecule (SLAM in oncolysis. Successful attempts to retarget MV by inserting genes for tumour-specific ligands to antigens such as carcinoembryonic antigen (CEA, CD20, CD38, and by engineering the virus to express synthetic microRNA targeting sequences, and “blinding” the virus to the natural viral receptors are exciting measures to increase viral specificity and enhance the oncolytic effect. Sodium iodine symporter (NIS can also be expressed by MV, which enables in vivo tracking of MV infection. Radiovirotherapy using MV-NIS, chemo-virotherapy to convert prodrugs to their toxic metabolites, and immune-virotherapy including incorporating antibodies against immune checkpoint inhibitors can also increase the oncolytic potential. Anti-viral host immune responses are a recognized barrier to the success of MV, and approaches such as transporting MV to the tumour sites by carrier cells, are showing promise. MV Clinical trials are producing encouraging preliminary results in ovarian cancer, myeloma and cutaneous non-Hodgkin lymphoma, and the outcome of currently open trials in glioblastoma multiforme, mesothelioma and squamous cell carcinoma are eagerly anticipated.

  5. Oncolytic herpes viruses, chemotherapeutics, and other cancer drugs.

    Science.gov (United States)

    Braidwood, Lynne; Graham, Sheila V; Graham, Alex; Conner, Joe

    2013-01-01

    Oncolytic viruses are emerging as a potential new way of treating cancers. They are selectively replication-competent viruses that propagate only in actively dividing tumor cells but not in normal cells and, as a result, destroy the tumor cells by consequence of lytic infection. At least six different oncolytic herpes simplex viruses (oHSVs) have undergone clinical trials worldwide to date, and they have demonstrated an excellent safety profile and intimations of efficacy. The first pivotal Phase III trial with an oHSV, talimogene laherparepvec (T-Vec [OncoVex(GM-CSF)]), is almost complete, with extremely positive early results reported. Intuitively, therapeutically beneficial interactions between oHSV and chemotherapeutic and targeted therapeutic drugs would be limited as the virus requires actively dividing cells for maximum replication efficiency and most anticancer agents are cytotoxic or cytostatic. However, combinations of such agents display a range of responses, with antagonistic, additive, or, perhaps most surprisingly, synergistic enhancement of antitumor activity. When synergistic interactions in cancer cell killing are observed, chemotherapy dose reductions that achieve the same overall efficacy may be possible, resulting in a valuable reduction of adverse side effects. Therefore, the combination of an oHSV with "standard-of-care" drugs makes a logical and reasonable approach to improved therapy, and the addition of a targeted oncolytic therapy with "standard-of-care" drugs merits further investigation, both preclinically and in the clinic. Numerous publications report such studies of oncolytic HSV in combination with other drugs, and we review their findings here. Viral interactions with cellular hosts are complex and frequently involve intracellular signaling networks, thus creating diverse opportunities for synergistic or additive combinations with many anticancer drugs. We discuss potential mechanisms that may lead to synergistic interactions.

  6. Clinical Considerations for Oncolytic Viral Therapies: A Regulatory Perspective.

    Science.gov (United States)

    Liu, K

    2017-05-01

    The US Food and Drug Administration (FDA) approved the first oncolytic viral therapy (OVT), Imlygic (talimogene laherparepvec), in October 2015 for the local treatment of unresectable cutaneous, subcutaneous, and nodal lesions in patients with melanoma recurrent after initial surgery, although talimogene has not been shown to improve overall survival or have an effect on visceral metastases. Published 2017. This article is a U.S. Government work and is in the public domain in the USA.

  7. Oncolytic VSV Primes Differential Responses to Immuno-oncology Therapy.

    Science.gov (United States)

    Durham, Nicholas M; Mulgrew, Kathy; McGlinchey, Kelly; Monks, Noel R; Ji, Hong; Herbst, Ronald; Suzich, JoAnn; Hammond, Scott A; Kelly, Elizabeth J

    2017-08-02

    Vesicular stomatitis virus encoding the IFNβ transgene (VSV-IFNβ) is a mediator of potent oncolytic activity and is undergoing clinical evaluation for the treatment of solid tumors. Emerging preclinical and clinical data suggest treatment of tumors with oncolytic viruses may sensitize tumors to checkpoint inhibitors and increase the anti-tumor immune response. New generations of immuno-oncology molecules including T cell agonists are entering clinical development and could be hypothesized to enhance the activity of oncolytic viruses, including VSV-IFNβ. Here, we show that VSV-IFNβ exhibits multiple mechanisms of action, including direct cell killing, stimulation of an innate immune response, recruitment of CD8 T cells, and depletion of T regulatory cells. Moreover, VSV-IFNβ promotes the establishment of a CD8 T cell response to endogenous tumor antigens. Our data demonstrate a significant enhancement of anti-tumor function for VSV-IFNβ when combined with checkpoint inhibitors, but not OX40 agonists. While the addition of checkpoint inhibitors to VSV-IFNβ generated robust tumor growth inhibition, it resulted in no increase in viral replication, transgene expression, or immunophenotypic changes beyond treatment with VSV-IFNβ alone. We hypothesize that tumor-specific T cells generated by VSV-IFNβ retain activity due to a lack of immune exhaustion when checkpoint inhibitors were used. Copyright © 2017 The American Society of Gene and Cell Therapy. Published by Elsevier Inc. All rights reserved.

  8. Analysis of HSV oncolytic virotherapy in organotypic cultures.

    Science.gov (United States)

    Fulci, Giulia; Passer, Brent

    2009-01-01

    Tumor-selective replication-competent viral vectors, such as oncolytic herpes simplex virus (HSV) type I (HSV-1), represent an attractive strategy for tumor-based therapies because these viruses can replicate and spread in situ exhibiting cytopathic effects through direct oncolytic activity. These lytic viruses offer a distinct advantage over other forms of cancer therapies in that they are self-perpetuating and can spread not only in the tumor itself, but also to distant micrometastases. Translational studies aimed at identifying novel virotherapies for human cancers are incumbent upon the appropriate experimental models. While animal models are the preferred choice for efficacy studies of HSV virotherapy, we have developed a novel complementary approach toward assessing the effectiveness of oncolytic HSV therapy in both brain and prostate cancers. This experimental model takes advantage of previously published work in which human prostate cancer biopsies and rodent brain slices can be easily maintained ex vivo. The advantage of these systems is that the three-dimensional structure remains intact. Thus, all of the factors that may affect viral entry and replication, such as cell-cell and cell-matrix interactions, and interstitial fluid within this three-dimensional milieu remain preserved. Moreover, with respect to the brain, this system offers the advantage of direct access to brain cells, such as microglia and astrocytes, and circumvents the problems associated with the presence of the blood-brain barrier.

  9. Oncolytic Replication of E1b-Deleted Adenoviruses

    Directory of Open Access Journals (Sweden)

    Pei-Hsin Cheng

    2015-11-01

    Full Text Available Various viruses have been studied and developed for oncolytic virotherapies. In virotherapy, a relatively small amount of viruses used in an intratumoral injection preferentially replicate in and lyse cancer cells, leading to the release of amplified viral particles that spread the infection to the surrounding tumor cells and reduce the tumor mass. Adenoviruses (Ads are most commonly used for oncolytic virotherapy due to their infection efficacy, high titer production, safety, easy genetic modification, and well-studied replication characteristics. Ads with deletion of E1b55K preferentially replicate in and destroy cancer cells and have been used in multiple clinical trials. H101, one of the E1b55K-deleted Ads, has been used for the treatment of late-stage cancers as the first approved virotherapy agent. However, the mechanism of selective replication of E1b-deleted Ads in cancer cells is still not well characterized. This review will focus on three potential molecular mechanisms of oncolytic replication of E1b55K-deleted Ads. These mechanisms are based upon the functions of the viral E1B55K protein that are associated with p53 inhibition, late viralmRNAexport, and cell cycle disruption.

  10. Aptamer-facilitated Protection of Oncolytic Virus from Neutralizing Antibodies.

    Science.gov (United States)

    Muharemagic, Darija; Zamay, Anna; Ghobadloo, Shahrokh M; Evgin, Laura; Savitskaya, Anna; Bell, John C; Berezovski, Maxim V

    2014-06-03

    Oncolytic viruses promise to significantly improve current cancer treatments through their tumor-selective replication and multimodal attack against cancer cells. However, one of the biggest setbacks for oncolytic virus therapy is the intravenous delivery of the virus, as it can be cleared from the bloodstream by neutralizing antibodies before it reaches the tumor cells. We have selected DNA aptamers against an oncolytic virus, vesicular stomatitis virus, using a competitive binding approach, as well as against the antigen binding fragment (Fab) of antivesicular stomatitis virus polyclonal antibodies, in order to shield the virus from nAbs and enhance its in vivo survival. We used flow cytometry to identify these aptamers and evaluated their efficiency to shield vesicular stomatitis virus in a cell-based plaque forming assay. These oligonucleotides were then modified to obtain multivalent binders, which led to a decrease of viral aggregation, an increase in its infectivity and an increase in its stability in serum. The aptamers were also incubated in nondiluted serum, showing their effectiveness under conditions mimicking those in vivo. With this approach, we were able to increase viral infectivity by more than 70% in the presence of neutralizing antibodies. Thus, this method has the potential to enhance the delivery of vesicular stomatitis virus through the bloodstream without compromising the patient's immune system.

  11. Modelling Spread of Oncolytic Viruses in Heterogeneous Cell Populations

    Science.gov (United States)

    Ellis, Michael; Dobrovolny, Hana

    2014-03-01

    One of the most promising areas in current cancer research and treatment is the use of viruses to attack cancer cells. A number of oncolytic viruses have been identified to date that possess the ability to destroy or neutralize cancer cells while inflicting minimal damage upon healthy cells. Formulation of predictive models that correctly describe the evolution of infected tumor systems is critical to the successful application of oncolytic virus therapy. A number of different models have been proposed for analysis of the oncolytic virus-infected tumor system, with approaches ranging from traditional coupled differential equations such as the Lotka-Volterra predator-prey models, to contemporary modeling frameworks based on neural networks and cellular automata. Existing models are focused on tumor cells and the effects of virus infection, and offer the potential for improvement by including effects upon normal cells. We have recently extended the traditional framework to a 2-cell model addressing the full cellular system including tumor cells, normal cells, and the impacts of viral infection upon both populations. Analysis of the new framework reveals complex interaction between the populations and potential inability to simultaneously eliminate the virus and tumor populations.

  12. Delta-24-RGD oncolytic adenovirus elicits anti-glioma immunity in an immunocompetent mouse model

    NARCIS (Netherlands)

    H. Jiang (Hao); K. Clise-Dwyer (Karen); K.E. Ruisaard (Kathryn); X. Fan (Xuejun); W. Tian (Weihua); J. Gumin (Joy); M.L.M. Lamfers (Martine); A. Kleijn (Anne); F.F. Lang (Frederick); S. Yung (Sun); L.M. Vence (Luis); C. Gomez-Manzano (Candelaria); J. Fueyo (Juan)

    2014-01-01

    textabstractBackground: Emerging evidence suggests anti-cancer immunity is involved in the therapeutic effect induced by oncolytic viruses. Here we investigate the effect of Delta-24-RGD oncolytic adenovirus on innate and adaptive anti-glioma immunity. Design: Mouse GL261-glioma model was set up in

  13. The Continued Promise and Many Disappointments of Oncolytic Virotherapy in Gastrointestinal Malignancies

    Directory of Open Access Journals (Sweden)

    Daniel H. Ahn

    2017-03-01

    Full Text Available Oncolytic virotherapy represents a novel therapeutic strategy in the treatment of gastrointestinal malignancies. Oncolytic viruses, including genetically engineered and naturally occurring viruses, can selectively replicate in and induce tumor cell apoptosis without harming normal tissues, thus offering a promising tool in the armamentarium for cancer therapy. While this approach has garnered much interest over the past several decades, there has not been significant headway across various tumor types. The recent approval of talimogene laherparepvec, a second-generation oncolytic herpes simplex virus type-1, for the treatment of metastatic melanoma, confirms the therapeutic potential of oncolytic viral therapy. Herein, we will highlight and review the role of oncolytic viral therapy in gastrointestinal malignancies while discussing its limitations and potential alternative mechanisms to improve its treatment efficacy.

  14. The Continued Promise and Many Disappointments of Oncolytic Virotherapy in Gastrointestinal Malignancies.

    Science.gov (United States)

    Ahn, Daniel H; Bekaii-Saab, Tanios

    2017-03-04

    Oncolytic virotherapy represents a novel therapeutic strategy in the treatment of gastrointestinal malignancies. Oncolytic viruses, including genetically engineered and naturally occurring viruses, can selectively replicate in and induce tumor cell apoptosis without harming normal tissues, thus offering a promising tool in the armamentarium for cancer therapy. While this approach has garnered much interest over the past several decades, there has not been significant headway across various tumor types. The recent approval of talimogene laherparepvec, a second-generation oncolytic herpes simplex virus type-1, for the treatment of metastatic melanoma, confirms the therapeutic potential of oncolytic viral therapy. Herein, we will highlight and review the role of oncolytic viral therapy in gastrointestinal malignancies while discussing its limitations and potential alternative mechanisms to improve its treatment efficacy.

  15. Oncolytic herpes viruses, chemotherapeutics, and other cancer drugs

    Directory of Open Access Journals (Sweden)

    Braidwood L

    2013-12-01

    Full Text Available Lynne Braidwood,1 Sheila V Graham,2 Alex Graham,1 Joe Conner11Virttu Biologics Ltd, Department of Neurology, Southern General Hospital, Glasgow, UK; 2MRC-University of Glasgow Centre for Virus Research, Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, Jarrett Building, University of Glasgow, Glasgow, UKAbstract: Oncolytic viruses are emerging as a potential new way of treating cancers. They are selectively replication-competent viruses that propagate only in actively dividing tumor cells but not in normal cells and, as a result, destroy the tumor cells by consequence of lytic infection. At least six different oncolytic herpes simplex viruses (oHSVs have undergone clinical trials worldwide to date, and they have demonstrated an excellent safety profile and intimations of efficacy. The first pivotal Phase III trial with an oHSV, talimogene laherparepvec (T-Vec [OncoVexGM-CSF], is almost complete, with extremely positive early results reported. Intuitively, therapeutically beneficial interactions between oHSV and chemotherapeutic and targeted therapeutic drugs would be limited as the virus requires actively dividing cells for maximum replication efficiency and most anticancer agents are cytotoxic or cytostatic. However, combinations of such agents display a range of responses, with antagonistic, additive, or, perhaps most surprisingly, synergistic enhancement of antitumor activity. When synergistic interactions in cancer cell killing are observed, chemotherapy dose reductions that achieve the same overall efficacy may be possible, resulting in a valuable reduction of adverse side effects. Therefore, the combination of an oHSV with “standard-of-care” drugs makes a logical and reasonable approach to improved therapy, and the addition of a targeted oncolytic therapy with “standard-of-care” drugs merits further investigation, both preclinically and in the clinic. Numerous publications report

  16. Norovirus recombination

    National Research Council Canada - National Science Library

    Bull, Rowena A; Tanaka, Mark M; White, Peter A

    2007-01-01

    ...{at}unsw.edu.au RNA recombination is a significant driving force in viral evolution. Increased awareness of recombination within the genus Norovirus of the family Calicivirus has led to a rise in the identification of norovirus (NoV...

  17. Vesicular stomatitis virus as a flexible platform for oncolytic virotherapy against cancer

    Science.gov (United States)

    Hastie, Eric

    2012-01-01

    Oncolytic virus (OV) therapy is an emerging anti-cancer approach that utilizes viruses to preferentially infect and kill cancer cells, while not harming healthy cells. Vesicular stomatitis virus (VSV) is a prototypic non-segmented, negative-strand RNA virus with inherent OV qualities. Antiviral responses induced by type I interferon pathways are believed to be impaired in most cancer cells, making them more susceptible to VSV than normal cells. Several other factors make VSV a promising OV candidate for clinical use, including its well-studied biology, a small, easily manipulated genome, relative independence of a receptor or cell cycle, cytoplasmic replication without risk of host-cell transformation, and lack of pre-existing immunity in humans. Moreover, various VSV-based recombinant viruses have been engineered via reverse genetics to improve oncoselectivity, safety, oncotoxicity and stimulation of tumour-specific immunity. Alternative delivery methods are also being studied to minimize premature immune clearance of VSV. OV treatment as a monotherapy is being explored, although many studies have employed VSV in combination with radiotherapy, chemotherapy or other OVs. Preclinical studies with various cancers have demonstrated that VSV is a promising OV; as a result, a human clinical trial using VSV is currently in progress. PMID:23052398

  18. Enhancing VSV oncolytic activity with an improved cytosine deaminase suicide gene strategy.

    Science.gov (United States)

    Leveille, S; Samuel, S; Goulet, M-L; Hiscott, J

    2011-06-01

    Oncolytic viruses (OVs) are promising therapeutic agents for cancer treatment, with recent studies emphasizing the combined use of chemotherapeutic compounds and prodrug suicide gene strategies to improve OV efficacy. In the present study, the synergistic activity of recombinant vesicular stomatitis virus (VSV)-MΔ51 virus expressing the cytosine deaminase/uracil phosphoribosyltransferase (CD::UPRT) suicide gene and 5-fluorocytosine (5FC) prodrug was investigated in triggering tumor cell oncolysis. In a panel of VSV-sensitive and -resistant cells-prostate PC3, breast MCF7 and TSA, B-lymphoma Karpas and melanoma B16-F10-the combination treatment increased killing of non-infected bystander cells in vitro via the release of 5FC toxic derivatives. In addition, we showed a synergistic effect on cancer cell killing with VSV-MΔ51 and the active form of the drug 5-fluorouracil. Furthermore, by monitoring VSV replication at the tumor site and maximizing 5FC bioavailability, we optimized the treatment regimen and improved survival of animals bearing TSA mammary adenocarcinoma. Altogether, this study emphasizes the potency of the VSV-CD::UPRT and 5FC combination, and demonstrates the necessity of optimizing each step of a multicomponent therapy to design efficient treatment.

  19. In vitro infectivity of oncolytic Newcastle Disease Virus: Correlation between plaque and fluorescent focus assays.

    Science.gov (United States)

    Rush, Benjamin S; Coughlin, Melissa L; Sanyal, Gautam

    2018-01-01

    Newcastle Disease Virus (NDV) is an avian paramyxovirus that has no significant pathogenicity in humans. Cancer cells with impaired immune defense mechanisms are susceptible to infection and lysis by NDV. A recombinant construct of a lentogenic form of NDV (rNDV) containing an insertion of granulocyte macrophage colony stimulating factor (GMCSF) transgene was earlier reported and shown to have acceptably low avian pathogenicity as well as oncolytic potential. Reliable measurement of infectious titer is key to determining the effectiveness of virus preparations to infect and lyse cells. We report here a comparative evaluation of two infectious titer assays as applied to rNDV: plaque assay and fluorescent focus assay (FFA). Optimization of assay conditions for both titer methods has produced concordant results spanning several orders of magnitude. While plaque formation is the gold standard measure of virus titer, FFA provides higher throughput and faster turn-around. FFA has been further evaluated on two different instrument platforms, for automated versus manual foci recognition and counting, with equivalent results. These results point to amenability of FFA to transfer between different laboratories and analysts, without introducing significant subjectivity in data analysis. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Vesicular stomatitis virus as a flexible platform for oncolytic virotherapy against cancer.

    Science.gov (United States)

    Hastie, Eric; Grdzelishvili, Valery Z

    2012-12-01

    Oncolytic virus (OV) therapy is an emerging anti-cancer approach that utilizes viruses to preferentially infect and kill cancer cells, while not harming healthy cells. Vesicular stomatitis virus (VSV) is a prototypic non-segmented, negative-strand RNA virus with inherent OV qualities. Antiviral responses induced by type I interferon pathways are believed to be impaired in most cancer cells, making them more susceptible to VSV than normal cells. Several other factors make VSV a promising OV candidate for clinical use, including its well-studied biology, a small, easily manipulated genome, relative independence of a receptor or cell cycle, cytoplasmic replication without risk of host-cell transformation, and lack of pre-existing immunity in humans. Moreover, various VSV-based recombinant viruses have been engineered via reverse genetics to improve oncoselectivity, safety, oncotoxicity and stimulation of tumour-specific immunity. Alternative delivery methods are also being studied to minimize premature immune clearance of VSV. OV treatment as a monotherapy is being explored, although many studies have employed VSV in combination with radiotherapy, chemotherapy or other OVs. Preclinical studies with various cancers have demonstrated that VSV is a promising OV; as a result, a human clinical trial using VSV is currently in progress.

  1. Complex spatial dynamics of oncolytic viruses in vitro: mathematical and experimental approaches.

    Directory of Open Access Journals (Sweden)

    Dominik Wodarz

    Full Text Available Oncolytic viruses replicate selectively in tumor cells and can serve as targeted treatment agents. While promising results have been observed in clinical trials, consistent success of therapy remains elusive. The dynamics of virus spread through tumor cell populations has been studied both experimentally and computationally. However, a basic understanding of the principles underlying virus spread in spatially structured target cell populations has yet to be obtained. This paper studies such dynamics, using a newly constructed recombinant adenovirus type-5 (Ad5 that expresses enhanced jellyfish green fluorescent protein (EGFP, AdEGFPuci, and grows on human 293 embryonic kidney epithelial cells, allowing us to track cell numbers and spatial patterns over time. The cells are arranged in a two-dimensional setting and allow virus spread to occur only to target cells within the local neighborhood. Despite the simplicity of the setup, complex dynamics are observed. Experiments gave rise to three spatial patterns that we call "hollow ring structure", "filled ring structure", and "disperse pattern". An agent-based, stochastic computational model is used to simulate and interpret the experiments. The model can reproduce the experimentally observed patterns, and identifies key parameters that determine which pattern of virus growth arises. The model is further used to study the long-term outcome of the dynamics for the different growth patterns, and to investigate conditions under which the virus population eliminates the target cells. We find that both the filled ring structure and disperse pattern of initial expansion are indicative of treatment failure, where target cells persist in the long run. The hollow ring structure is associated with either target cell extinction or low-level persistence, both of which can be viewed as treatment success. Interestingly, it is found that equilibrium properties of ordinary differential equations describing the

  2. Safety and infectivity of two doses of live-attenuated recombinant cold-passaged human parainfluenza type 3 virus vaccine rHPIV3cp45 in HPIV3-seronegative young children.

    Science.gov (United States)

    Englund, Janet A; Karron, Ruth A; Cunningham, Coleen K; Larussa, Philip; Melvin, Ann; Yogev, Ram; Handelsman, Ed; Siberry, George K; Thumar, Bhavanji; Schappell, Elizabeth; Bull, Catherine V; Chu, Helen Y; Schaap-Nutt, Anne; Buchholz, Ursula; Collins, Peter L; Schmidt, Alexander C

    2013-11-19

    Human parainfluenza virus type 3 (HPIV3) is a common cause of upper and lower respiratory tract illness in infants and young children. Live-attenuated cold-adapted HPIV3 vaccines have been evaluated in infants but a suitable interval for administration of a second dose of vaccine has not been defined. HPIV3-seronegative children between the ages of 6 and 36 months were randomized 2:1 in a blinded study to receive two doses of 10⁵ TCID₅₀ (50% tissue culture infectious dose) of live-attenuated, recombinant cold-passaged human PIV3 vaccine (rHPIV3cp45) or placebo 6 months apart. Serum antibody levels were assessed prior to and approximately 4-6 weeks after each dose. Vaccine virus infectivity, defined as detection of vaccine-HPIV3 in nasal wash and/or a≥4-fold rise in serum antibody titer, and reactogenicity were assessed on days 3, 7, and 14 following immunization. Forty HPIV3-seronegative children (median age 13 months; range 6-35 months) were enrolled; 27 (68%) received vaccine and 13 (32%) received placebo. Infectivity was detected in 25 (96%) of 26 evaluable vaccinees following doses 1 and 9 of 26 subject (35%) following dose 2. Among those who shed virus, the median duration of viral shedding was 12 days (range 6-15 days) after dose 1 and 6 days (range 3-8 days) after dose 2, with a mean peak log₁₀ viral titer of 3.4 PFU/mL (SD: 1.0) after dose 1 compared to 1.5 PFU/mL (SD: 0.92) after dose 2. Overall, reactogenicity was mild, with no difference in rates of fever and upper respiratory infection symptoms between vaccine and placebo groups. rHPIV3cp45 was immunogenic and well-tolerated in seronegative young children. A second dose administered 6 months after the initial dose was restricted in those previously infected with vaccine virus; however, the second dose boosted antibody responses and induced antibody responses in two previously uninfected children. Copyright © 2013 Elsevier Ltd. All rights reserved.

  3. The current status of oncolytic viral therapy for head and neck cancer

    Directory of Open Access Journals (Sweden)

    Matthew O. Old

    2016-06-01

    Full Text Available Objective: Cancer affects the head and neck region frequently and leads to significant morbidity and mortality. Oncolytic viral therapy has the potential to make a big impact in cancers that affect the head and neck. We intend to review the current state of oncolytic viruses in the treatment of cancers that affect the head and neck region. Method: Data sources are from National clinical trials database, literature, and current research. Results: There are many past and active trials for oncolytic viruses that show promise for treating cancers of the head and neck. The first oncolytic virus was approved by the FDA October 2015 (T-VEC, Amgen for the treatment of melanoma. Active translational research continues for this and many other oncolytic viruses. Conclusion: The evolving field of oncolytic viruses is impacting the treatment of head and neck cancer and further trials and agents are moving forward in the coming years. Keywords: Head and neck squamous cell carcinoma, Oncolytic viruses, Clinical trials, Novel therapeutics

  4. Oncolytic Herpes Simplex Viral Therapy: A Stride toward Selective Targeting of Cancer Cells.

    Science.gov (United States)

    Sanchala, Dhaval S; Bhatt, Lokesh K; Prabhavalkar, Kedar S

    2017-01-01

    Oncolytic viral therapy, which makes use of replication-competent lytic viruses, has emerged as a promising modality to treat malignancies. It has shown meaningful outcomes in both solid tumor and hematologic malignancies. Advancements during the last decade, mainly genetic engineering of oncolytic viruses have resulted in improved specificity and efficacy of oncolytic viruses in cancer therapeutics. Oncolytic viral therapy for treating cancer with herpes simplex virus-1 has been of particular interest owing to its range of benefits like: (a) large genome and power to infiltrate in the tumor, (b) easy access to manipulation with the flexibility to insert multiple transgenes, (c) infecting majority of the malignant cell types with quick replication in the infected cells and (d) as Anti-HSV agent to terminate HSV replication. This review provides an exhaustive list of oncolytic herpes simplex virus-1 along with their genetic alterations. It also encompasses the major developments in oncolytic herpes simplex-1 viral therapy and outlines the limitations and drawbacks of oncolytic herpes simplex viral therapy.

  5. Current status of clinical trials assessing oncolytic virus therapy for urological cancers.

    Science.gov (United States)

    Taguchi, Satoru; Fukuhara, Hiroshi; Homma, Yukio; Todo, Tomoki

    2017-05-01

    Oncolytic virus therapy has recently been recognized as a promising new option for cancer treatment. Oncolytic viruses replicate selectively in cancer cells, thus killing them without harming normal cells. Notably, T-VEC (talimogene laherparepvec, formerly called OncoVEX(GM)(-)(CSF) ), an oncolytic herpes simplex virus type 1, was approved by the US Food and Drug Administration for the treatment of inoperable melanoma in October 2015, and was subsequently approved in Europe and Australia in 2016. The efficacies of many types of oncolytic viruses against urological cancers have been investigated in preclinical studies during the past decade, and some have already been tested in clinical trials. For example, a phase I trial of the third-generation oncolytic Herpes simplex virus type 1, G47Δ, in patients with prostate cancer was completed in 2016. We summarize the current status of clinical trials of oncolytic virus therapy in patients with the three major urological cancers: prostate, bladder and renal cell cancers. In addition to Herpes simplex virus type 1, adenoviruses, reoviruses, vaccinia virus, Sendai virus and Newcastle disease virus have also been used as parental viruses in these trials. We believe that oncolytic virus therapy is likely to become an important and major treatment option for urological cancers in the near future. © 2017 The Japanese Urological Association.

  6. A novel oncolytic adenovirus based on simian adenovirus serotype 24.

    Science.gov (United States)

    Cheng, Tao; Song, Yufeng; Zhang, Yan; Zhang, Chao; Yin, Jieyun; Chi, Yudan; Zhou, Dongming

    2017-04-18

    Among the oncolytic virotherapy, an emerging treatment for tumor, adenoviruses are widely used at present in preclinical and clinical trials. Traditionally, oncolytic adenoviruses were developed based on the human adenovirus serotype 5 (AdHu5). However, AdHu5 has the drawbacks of preexisting anti-AdHu5 immunity in most populations, and extensive sequestration of Adhu5 by the liver through hexon, blood coagulation factor X (FX), and FX receptor interactions. To tackle these problems, we explored a novel oncolytic adenovirus AdC7-SP/E1A-ΔE3 for cancer treatment. AdC7-SP/E1A-ΔE3 was constructed by replacing the E1A promoter with tumor specific promoter survivin promoter and deleting E3 region using direct cloning methods based on simian adenovirus serotype 24 (namely AdC7). We showed that AdC7-SP/E1A-ΔE3 significantly killed tumor cell lines NCI-H508 and Huh7, and inhibited tumor growth in both NCI-H508 and Huh7 xenograft tumor models. Importantly, AdC7-SP/E1A-ΔE3 exhibited the antitumor efficacy via systemic administration. Mechanistically, infected cells were killed by AdC7-SP/E1A-ΔE3 via the p53-independent mitochondrial apoptosis pathway in which phosphorylation of BAD markedly declined and the expresses of Bik significantly went up. Therefore, AdC7-SP/E1A-ΔE3 is a promising candidate for liver and colon tumor treatment.

  7. Oncolytic virotherapy using herpes simplex virus: how far have we come?

    Science.gov (United States)

    Sokolowski, Nicolas As; Rizos, Helen; Diefenbach, Russell J

    2015-01-01

    Oncolytic virotherapy exploits the properties of human viruses to naturally cytolysis of cancer cells. The human pathogen herpes simplex virus (HSV) has proven particularly amenable for use in oncolytic virotherapy. The relative safety of HSV coupled with extensive knowledge on how HSV interacts with the host has provided a platform for manipulating HSV to enhance the targeting and killing of human cancer cells. This has culminated in the approval of talimogene laherparepvec for the treatment of melanoma. This review focuses on the development of HSV as an oncolytic virus and where the field is likely to head in the future.

  8. Identification of host range mutants of myxoma virus with altered oncolytic potential in human glioma cells.

    Science.gov (United States)

    Barrett, John W; Alston, Lindsay R; Wang, Fuan; Stanford, Marianne M; Gilbert, Philippe-Alexandre; Gao, Xiujuan; Jimenez, June; Villeneuve, Danielle; Forsyth, Peter; McFadden, Grant

    2007-12-01

    The authors have recently demonstrated that wild-type myxoma virus (MV) tagged with gfp (vMyxgfp) can generate a tumor-specific infection that productively infects and clears human tumor-derived xenografts when injected intratumorally into human gliomas transplanted into immunodeficient mice (Lun et al, 2005). To expand the understanding of MV tropism in cancer cells from a specific tissue lineage, the authors have screened a series of human glioma cells (U87, U118, U251, U343, U373) for myxoma virus replication and oncolysis. To assess the viral tropism determinants for these infections, the authors have screened myxoma virus knockout constructs that have been deleted for specific host range genes (M-T2, M-T4, M-T5, M11L, and M063), as well as a control MV gene knockout construct with no known host range function (vMyx135KO) but is highly attenuated in rabbits. The authors report wide variation in the ability of various vMyx-hrKOs to replicate and spread in the human glioma cells as measured by early and late viral gene expression. This differential ability to support vMyx-hrKO productive viral replication is consistent with levels of endogenous activated Akt in the various gliomas. The authors have identified one vMyx-hrKO virus (vMyx63KO) and one nonhost range knockout construct (vMyx135KO) that appear to replicate in the gliomas even more efficiently than the wild-type virus and that reduce the viability of the infected gliomas. These knockout viruses also inhibit the proliferation of gliomas in a manner similar to the wild-type virus. Together these data, as well as the fact that these knockout viruses are attenuated in their natural hosts, may represent environmentally safer candidate oncolytic viruses for usage in human trials.

  9. An armed, YB-1-dependent oncolytic adenovirus as a candidate for a combinatorial anti-glioma approach of virotherapy, suicide gene therapy and chemotherapeutic treatment.

    Science.gov (United States)

    Kostova, Y; Mantwill, K; Holm, P S; Anton, M

    2015-01-01

    We investigated the novel recombinant oncolytic adenovirus Ad-delo-sr39TK-RGD, armed with a mutant herpes simplex virus type 1 thymidine kinase (HSV1-sr39TK) as a suicide gene, and explored its antitumor efficacy in combination with HSV1-sr39TK/ganciclovir (GCV) gene therapy and temozolomide (TMZ). Ad-delo-sr39TK-RGD is an E1-mutated conditionally replicating adenovirus dependent on the human Y-box binding protein 1 (YB-1). Thus, we utilized the YB-1 dependency of the vector to target human glioma cells in vitro, using two-dimensional cell culture and three-dimensional multicellular spheroids, and demonstrated the strong replication competence and oncolytic potential of the virus. The cytotoxicity mediated by HSV1-sr39TK and its prodrug GCV enhanced the oncolytic effect even at 95% after adding GCV 0-1 days following infection. An increased bystander effect of viral replication and GCV in co-cultured infected and uninfected cells was observed. Co-administrating Ad-delo-sr39TK-RGD with TMZ and GCV, spheroid growth was reduced drastically. Gamma counting of infected spheroids demonstrated successful accumulation of the radiotracer (18)F-labeled 9-[4-fluoro-3-(hydroxymethyl)butyl]guanine mediated by HSV1-sr39TK. Hence, our results show that the combination of YB-1-dependent virotherapy with suicide genes and TMZ effectively induces glioma cell killing and may allow for in vivo non-invasive imaging within a limited time frame.

  10. Pediatric glioma stem cells: biologic strategies for oncolytic HSV virotherapy

    Directory of Open Access Journals (Sweden)

    Gregory K Friedman

    2013-02-01

    Full Text Available While glioblastoma multiforme (GBM is the most common adult malignant brain tumor, GBMs in childhood represent less than 10% of pediatric malignant brain tumors and are phenotypically and molecularly distinct from adult GBMs. Similar to adult patients, outcomes for children with high-grade gliomas (HGGs remain poor. Furthermore, the significant morbidity and mortality yielded by pediatric GBM is compounded by neurotoxicity for the developing brain caused by current therapies. Poor outcomes have been attributed to a subpopulation of chemotherapy and radiotherapy resistant cells, termed ‘glioma stem cells’ (GSCs, ‘glioma progenitor cells’, or ‘glioma-initiating cells', which have the ability to initiate and maintain the tumor and to repopulate the recurring tumor after conventional therapy. Future innovative therapies for pediatric HGGs must be able to eradicate these therapy-resistant GSCs. Oncolytic herpes simplex viruses, genetically engineered to be safe for normal cells and to express diverse foreign anti-tumor therapeutic genes, have been demonstrated in preclinical studies to infect and kill GSCs and tumor cells equally while sparing normal brain cells. In this review, we discuss the unique aspects of pediatric GSCs, including markers to identify them, the microenvironment they reside in, signaling pathways that regulate them, mechanisms of cellular resistance, and approaches to target GSCs, with a focus on the promising therapeutic, genetically engineered oncolytic herpes simplex virus (HSV.

  11. ONCOLYTIC VIRUS-MEDIATED REVERSAL OF IMPAIRED TUMOR ANTIGEN PRESENTATION

    Directory of Open Access Journals (Sweden)

    Shashi Ashok Gujar

    2014-04-01

    Full Text Available Anti-tumor immunity can eliminate existing cancer cells and also maintain a constant surveillance against possible relapse. Such an antigen-specific adaptive response begins when tumor-specific T cells become activated. T cell activation requires two signals on antigen presenting cells (APCs: antigen presentation through MHC molecules and co-stimulation. In the absence of one or both of these signals, T cells remain inactivated or can even become tolerized. Cancer cells and their associated microenvironment strategically hinder the processing and presentation of tumor antigens and consequently prevent the development of anti-tumor immunity. Many studies, however, demonstrate that interventions that overturn tumor-associated immune evasion mechanisms can establish anti-tumor immune responses of therapeutic potential. One such intervention is oncolytic virus (OV-based anti-cancer therapy. Here we discuss how OV-induced immunological events override tumor-associated antigen presentation impairment and promote appropriate T cell:APC interaction. Detailed understanding of this phenomenon is pivotal for devising the strategies that will enhance the efficacy of OV-based anti-cancer therapy by complementing its inherent oncolytic

  12. Myxoma virus is oncolytic for human pancreatic adenocarcinoma cells.

    Science.gov (United States)

    Woo, Yanghee; Kelly, Kaitlyn J; Stanford, Marianne M; Galanis, Charles; Chun, Yun Shin; Fong, Yuman; McFadden, Grant

    2008-08-01

    Viral oncolytic therapy, which seeks to exploit the use of live viruses to treat cancer, has shown promise in the treatment of cancers resistant to conventional anticancer therapies. Among the most difficult to treat cancers is advanced pancreatic adenocarcinoma. Our study investigates the ability of a novel oncolytic agent, myxoma virus, to infect, productively replicate in, and kill human pancreatic cancer cells in vitro. The myxoma virus vMyxgfp was tested against a panel of human pancreatic adenocarcinoma cell lines. Infectivity, viral proliferation, and tumor cell kill were assessed. Infection of tumor cells was assessed by expression of the marker gene enhanced green fluorescent protein (e-GFP). vMyxgfp had the ability to infect all pancreatic cancer cell lines tested. Killing of tumor cells varied among the 6 cell lines tested, ranging from >90% cell kill at 7 days for the most sensitive Panc-1 cells, to 39% in the most resistant cell line Capan-2. Sensitivity correlated to replication of virus, and was found to maximally exhibit a four-log increase in foci-forming units for the most sensitive Panc-1 cells within 72 h. Our study demonstrates for the first time the ability of the myxoma virus to productively infect, replicate in, and lyse human pancreatic adenocarcinoma cells in vitro. These data encourage further investigation of this virus, which is pathogenic only in rabbits, for treatment of this nearly uniformly fatal cancer.

  13. Questing for an optimal, universal viral agent for oncolytic virotherapy

    Science.gov (United States)

    Paiva, L. R.; Martins, M. L.; Ferreira, S. C.

    2011-10-01

    One of the most promising strategies to treat cancer is attacking it with viruses designed to exploit specific altered pathways. Here, the effects of oncolytic virotherapy on tumors having compact, papillary, and disconnected morphologies are investigated through computer simulations of a multiscale model coupling macroscopic reaction-diffusion equations for the nutrients with microscopic stochastic rules for the actions of individual cells and viruses. The interaction among viruses and tumor cells involves cell infection, intracellular virus replication, and the release of new viruses in the tissue after cell lysis. The evolution over time of both the viral load and cancer cell population, as well as the probabilities for tumor eradication, were evaluated for a range of multiplicities of infection, viral entries, and burst sizes. It was found that in immunosuppressed hosts, the antitumor efficacy of a virus is primarily determined by its entry efficiency, its replicative capacity within the tumor, and its ability to spread over the tissue. However, the optimal traits for oncolytic viruses depend critically on the tumor growth dynamics and do not necessarily include rapid replication, cytolysis, or spreading, currently assumed as necessary conditions for a successful therapeutic outcome. Our findings have potential implications on the design of new vectors for the viral therapy of cancer.

  14. Oncolytic virus therapy for cancer: the first wave of translational clinical trials.

    Science.gov (United States)

    Patel, Manish R; Kratzke, Robert A

    2013-04-01

    The field of oncolytic virus therapy, the use of live, replicating viruses for the treatment of cancer, has expanded rapidly over the past decade. Preclinical models have clearly demonstrated anticancer activity against a number of different cancer types. Several agents have entered clinical trials and promising results have led to late stage clinical development for some viruses. The early clinical trials have demonstrated that oncolytic viruses by themselves have potential to result in tumor regression. Engineering of viruses to express novel genes have also led to the use of these vectors as a novel form of gene therapy. As a result, interest in oncolytic virus therapy has gained traction. The following review will focus on the first wave of clinical translation of oncolytic virus therapy, what has been learned so far, and potential challenges ahead for advancing the field. Copyright © 2013 Mosby, Inc. All rights reserved.

  15. Potent Oncolytic Herpes Simplex Virus for the Therapy of Advanced Prostate Cancer

    National Research Council Canada - National Science Library

    Zhang, Xiaoliu

    2007-01-01

    .... We proposed to develop a novel virotherapy for prostate cancer during the funding period. Our working hypothesis was that a fusogenic oncolytic virus would induce a widespread syncytia formation...

  16. Pharmacological modulation of anti-tumor immunity induced by oncolytic viruses

    Directory of Open Access Journals (Sweden)

    Nicole E. Forbes

    2014-07-01

    Full Text Available Oncolytic viruses kill cancer cells by direct lysis but also generate a significant anti-tumor immune response that allows for prolonged cancer control and in some cases cures. How to best stimulate this effect is a subject of intense investigation in the oncolytic virus field. While pharmacological manipulation of the cellular innate antiviral immune response has been shown by several groups to improve viral oncolysis and spread, it is increasingly clear that pharmacological agents can also impact the anti-tumor immune response generated by oncolytic viruses and related tumor vaccination strategies. This review covers recent progress in using pharmacological agents to improve the activity of oncolytic viruses and their ability to generate robust anti-tumor immune responses.

  17. A Fusogenic Oncolytic Herpes Simplex Virus for Therapy of Advanced Ovarian Cancer

    National Research Council Canada - National Science Library

    Zhang, Xiaoliu

    2004-01-01

    The tasks that were originally planned for the first year of this 3 year project are to demonstrate that the fusogenic oncolytic herpes simplex viruses are potent anti-tumor agents for advanced ovarian cancer...

  18. Myxoma virus suppresses proliferation of activated T lymphocytes yet permits oncolytic virus transfer to cancer cells

    OpenAIRE

    Villa, Nancy Y.; Wasserfall, Clive H.; Meacham, Amy M.; Wise, Elizabeth; Chan, Winnie; Wingard, John R; McFadden, Grant; Cogle, Christopher R.

    2015-01-01

    MYXV binds human T lymphocytes but does not enter and infect T cells until after activation.MYXV-infected T lymphocytes proliferate less and secrete less inflammatory cytokines but deliver oncolytic virus to augment GVM.

  19. Genetic Recombination

    Science.gov (United States)

    Whitehouse, H. L. K.

    1973-01-01

    Discusses the mechanisms of genetic recombination with particular emphasis on the study of the fungus Sordaria brevicollis. The study of recombination is facilitated by the use of mutants of this fungus in which the color of the ascospores is affected. (JR)

  20. A Fusogenic Oncolytic Herpes Simplex Virus for Therapy of Advanced Ovarian Cancer

    Science.gov (United States)

    2007-06-01

    a single oncolytic HSV, might significantly improve virotherapy for ovarian cancer . Results: In vitro characterization of a doubly fusogenic...candidate for in vivo virotherapy against advanced ovarian cancer . MATERIALS AND METHODS Cell Lines and Mice. African green monkey kidney cells (Vero) were...viruses as oncolytic agents for human malignant brain tumors. Cancer Res., 57: 1502–1509, 1997. 14. Fu, X., and Zhang, X. Potent systemic antitumor

  1. Oncolytic virus therapy: A new era of cancer treatment at dawn.

    Science.gov (United States)

    Fukuhara, Hiroshi; Ino, Yasushi; Todo, Tomoki

    2016-10-01

    Oncolytic virus therapy is perhaps the next major breakthrough in cancer treatment following the success in immunotherapy using immune checkpoint inhibitors. Oncolytic viruses are defined as genetically engineered or naturally occurring viruses that selectively replicate in and kill cancer cells without harming the normal tissues. T-Vec (talimogene laherparepvec), a second-generation oncolytic herpes simplex virus type 1 (HSV-1) armed with GM-CSF, was recently approved as the first oncolytic virus drug in the USA and Europe. The phase III trial proved that local intralesional injections with T-Vec in advanced malignant melanoma patients can not only suppress the growth of injected tumors but also act systemically and prolong overall survival. Other oncolytic viruses that are closing in on drug approval in North America and Europe include vaccinia virus JX-594 (pexastimogene devacirepvec) for hepatocellular carcinoma, GM-CSF-expressing adenovirus CG0070 for bladder cancer, and Reolysin (pelareorep), a wild-type variant of reovirus, for head and neck cancer. In Japan, a phase II clinical trial of G47∆, a third-generation oncolytic HSV-1, is ongoing in glioblastoma patients. G47∆ was recently designated as a "Sakigake" breakthrough therapy drug in Japan. This new system by the Japanese government should provide G47∆ with priority reviews and a fast-track drug approval by the regulatory authorities. Whereas numerous oncolytic viruses have been subjected to clinical trials, the common feature that is expected to play a major role in prolonging the survival of cancer patients is an induction of specific antitumor immunity in the course of tumor-specific viral replication. It appears that it will not be long before oncolytic virus therapy becomes a standard therapeutic option for all cancer patients. © 2016 The Authors. Cancer Science published by John Wiley & Sons Australia, Ltd on behalf of Japanese Cancer Association.

  2. Oncolytic effects of a novel influenza A virus expressing interleukin-15 from the NS reading frame.

    Directory of Open Access Journals (Sweden)

    Marijke van Rikxoort

    Full Text Available Oncolytic influenza A viruses with deleted NS1 gene (delNS1 replicate selectively in tumour cells with defective interferon response and/or activated Ras/Raf/MEK/ERK signalling pathway. To develop a delNS1 virus with specific immunostimulatory properties, we used an optimised technology to insert the interleukin-15 (IL-15 coding sequence into the viral NS gene segment (delNS1-IL-15. DelNS1 and delNS1-IL-15 exerted similar oncolytic effects. Both viruses replicated and caused caspase-dependent apoptosis in interferon-defective melanoma cells. Virus replication was required for their oncolytic activity. Cisplatin enhanced the oncolytic activity of delNS1 viruses. The cytotoxic drug increased delNS1 replication and delNS1-induced caspase-dependent apoptosis. Interference with MEK/ERK signalling by RNAi-mediated depletion or the MEK inhibitor U0126 did not affect the oncolytic effects of the delNS1 viruses. In oncolysis sensitive melanoma cells, delNS1-IL-15 (but not delNS1 infection resulted in the production of IL-15 levels ranging from 70 to 1140 pg/mL in the cell culture supernatants. The supernatants of delNS1-IL-15-infected (but not of delNS1-infected melanoma cells induced primary human natural killer cell-mediated lysis of non-infected tumour cells. In conclusion, we constructed a novel oncolytic influenza virus that combines the oncolytic activity of delNS1 viruses with immunostimulatory properties through production of functional IL-15. Moreover, we showed that the oncolytic activity of delNS1 viruses can be enhanced in combination with cytotoxic anti-cancer drugs.

  3. Oncolytic viruses on the cusp of success?: proceedings of the 9th International Conference on Oncolytic Virus Therapeutics

    Directory of Open Access Journals (Sweden)

    Cole Peters

    2016-01-01

    Full Text Available Boston, Massachusetts, was the site of the 9th International Conference on Oncolytic Virus Therapeutics held 13–16 June 2015. An overarching theme of the meeting was the continued development of combinatorial treatment regimens to bolster the therapeutic potential of oncolytic viruses (OVs. Several talks focused on combining OVs with immune checkpoint inhibitors in a wide array of tumors, signaling an experimental and thematic shift toward driving immune activation to clear a tumor versus relying on direct viral oncolysis. An important aspect of the meeting was the variety of ongoing OV clinical trials. Topics ranged from basic virology to clinical trials and from academic research to intellectual property and biotechnology. There was much excitement due to the US Food and Drug Administration’s recent consideration of talimogene laherparepvec (T-VEC for the treatment of advanced melanoma (T-VEC was approved in October, following the conference. Here, we summarize the meeting’s primary themes, which reflect the current state of the field.

  4. Smac mimetics and oncolytic viruses synergize in driving anticancer T-cell responses through complementary mechanisms.

    Science.gov (United States)

    Kim, Dae-Sun; Dastidar, Himika; Zhang, Chunfen; Zemp, Franz J; Lau, Keith; Ernst, Matthias; Rakic, Andrea; Sikdar, Saif; Rajwani, Jahanara; Naumenko, Victor; Balce, Dale R; Ewanchuk, Ben W; Taylor, Pankaj; Yates, Robin M; Jenne, Craig; Gafuik, Chris; Mahoney, Douglas J

    2017-08-24

    Second mitochondrial activator of caspase (Smac)-mimetic compounds and oncolytic viruses were developed to kill cancer cells directly. However, Smac-mimetic compound and oncolytic virus therapies also modulate host immune responses in ways we hypothesized would complement one another in promoting anticancer T-cell immunity. We show that Smac-mimetic compound and oncolytic virus therapies synergize in driving CD8 + T-cell responses toward tumors through distinct activities. Smac-mimetic compound treatment with LCL161 reinvigorates exhausted CD8 + T cells within immunosuppressed tumors by targeting tumor-associated macrophages for M1-like polarization. Oncolytic virus treatment with vesicular stomatitis virus (VSV ΔM51 ) promotes CD8 + T-cell accumulation within tumors and CD8 + T-cell activation within the tumor-draining lymph node. When combined, LCL161 and VSV ΔM51 therapy engenders CD8 + T-cell-mediated tumor control in several aggressive mouse models of cancer. Smac-mimetic compound and oncolytic virus therapies are both in clinical development and their combination therapy represents a promising approach for promoting anticancer T-cell immunity.Oncolytic viruses (OV) and second mitochondrial activator of caspase (Smac)-mimetic compounds (SMC) synergistically kill cancer cells directly. Here, the authors show that SMC and OV therapies combination also synergize in vivo by promoting anticancer immunity through an increase in CD8 + T-cell response.

  5. Employing RNA viruses to fight cancer: novel insights into oncolytic virotherapy.

    Science.gov (United States)

    Masemann, Dörthe; Boergeling, Yvonne; Ludwig, Stephan

    2017-07-26

    Within recent decades, viruses that specifically target tumor cells have emerged as novel therapeutic agents against cancer. These viruses do not only act via their cell-lytic properties, but also harbor immunostimulatory features to re-direct the tumor microenvironment and stimulate tumor-directed immune responses. Furthermore, oncolytic viruses are considered to be superior to classical cancer therapies due to higher selectivity towards tumor cell destruction and, consequently, less collateral damage of non-transformed healthy tissue. In particular, the field of oncolytic RNA viruses is rapidly developing since these agents possess alternative tumor-targeting strategies compared to established oncolytic DNA viruses. Thus, oncolytic RNA viruses have broadened the field of virotherapy facilitating new strategies to fight cancer. In addition to several naturally occurring oncolytic viruses, genetically modified RNA viruses that are armed to express foreign factors such as immunostimulatory molecules have been successfully tested in early clinical trials showing promising efficacy. This review aims to provide an overview of the most promising RNA viruses in clinical development, to summarize the current knowledge of clinical trials using these viral agents, and to discuss the main issues as well as future perspectives of clinical approaches using oncolytic RNA viruses.

  6. Fusogenic oncolytic herpes simplex viruses as a potent and personalized cancer vaccine.

    Science.gov (United States)

    Li, Qi-Xiang; Liu, Guohong; Zhang, Xiaoliu

    2012-07-01

    The recent FDA approval of Sipuleucel-T for the treatment of prostate cancer represents an important milestone of cancer immunotherapy, which, for the first time, validates the concept of bringing true clinical benefit to cancer patients by stimulating patients' own anti-tumor immunity. Among the different experimental cancer immunotherapies, oncolytic virotherapy may represent a low-cost yet potent and personalized cancer vaccine for the treatment of solid tumors. This review describes the constructions of several human herpes simplex virus (HSV)-derived oncolytic viruses as candidate cancer vaccines, which induce specific and potent anti-tumor immunity in pre-clinical models, and thus resulting in stronger overall anti-tumor efficacy as compared to oncolytic effect alone. This article also describes the approaches to enhance the antitumor immunity of oncolytic HSVs, and in particular, the key role played by integrating membrane-fusion activity into these viruses. Additionally, this article reviews the potential effect of certain chemotherapeutic agents (e.g. cyclophosphamide) in boosting antitumor immunity induced by oncolytic HSV, and the mechanisms behind it. In summary, all the preclinical and clinical data have suggested that HSV-based oncolytic virotherapies could likely be developed as a new generation of cancer vaccines for the treatment of solid tumors.

  7. Recombination monitor

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, S. Y. [Brookhaven National Lab. (BNL), Upton, NY (United States); Blaskiewicz, M. [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2017-02-03

    This is a brief report on LEReC recombination monitor design considerations. The recombination produced Au78+ ion rate is reviewed. Based on this two designs are discussed. One is to use the large dispersion lattice. It is shown that even with the large separation of the Au78+ beam from the Au79+ beam, the continued monitoring of the recombination is not possible. Accumulation of Au78+ ions is needed, plus collimation of the Au79+ beam. In another design, it is shown that the recombination monitor can be built based on the proposed scheme with the nominal lattice. From machine operation point of view, this design is preferable. Finally, possible studies and the alternative strategies with the basic goal of the monitor are discussed.

  8. Questing for an optimal, universal viral agent for oncolytic virotherapy

    CERN Document Server

    Paiva, L R; Ferreira, S C

    2011-01-01

    One of the most promising strategies to treat cancer is attacking it with viruses designed to exploit specific altered pathways. Here, the effects of oncolytic virotherapy on tumors having compact, papillary and disconnected morphologies are investigated through computer simulations of a multiscale model coupling macroscopic reaction diffusion equations for the nutrients with microscopic stochastic rules for the actions of individual cells and viruses. The interaction among viruses and tumor cells involves cell infection, intracellular virus replication and release of new viruses in the tissue after cell lysis. The evolution in time of both viral load and cancer cell population, as well as the probabilities for tumor eradication were evaluated for a range of multiplicities of infection, viral entries and burst sizes. It was found that in immunosuppressed hosts, the antitumor efficacy of a virus is primarily determined by its entry efficiency, its replicative capacity within the tumor, and its ability to sprea...

  9. Oncolytic Viruses: The Best is Yet to Come.

    Science.gov (United States)

    Lemay, Chantal G; Keller, Brian A; Edge, Robert E; Abei, Masato; Bell, John C

    2017-02-06

    Oncolytic viruses are a promising anti-cancer platform, achieving significant pre-clinical and clinical milestones in recent years. A full arsenal of selective, safe, and effective viruses has been developed with some emerging pre-clinical research focusing on optimizing these therapies in the face of remaining challenges, both in the bloodstream and in the tumour microenvironment. Herein we discuss the recent progress in pre-clinical virotherapy research to address these challenges, with special focus on innovative strategies that seek to complement the current strengths of virotherapy, ensuring an optimal multi-faceted attack on cancer. This review highlights the research areas that we believe provide the most potential to increase the efficacy of this exciting biotherapy platform: cell carriers, tumour vascular destruction, microenvironment modulation, combination therapies, and virus-mediated anti-tumour immune responses. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  10. Oncolytic viruses and their application to cancer immunotherapy.

    Science.gov (United States)

    Chiocca, E Antonio; Rabkin, Samuel D

    2014-04-01

    Oncolytic viruses (OV) selectively replicate and kill cancer cells and spread within the tumor, while not harming normal tissue. In addition to this direct oncolytic activity, OVs are also very effective at inducing immune responses to themselves and to the infected tumor cells. OVs encompass a broad diversity of DNA and RNA viruses that are naturally cancer selective or can be genetically engineered. OVs provide a diverse platform for immunotherapy; they act as in situ vaccines and can be armed with immunomodulatory transgenes or combined with other immunotherapies. However, the interactions of OVs with the immune system may affect therapeutic outcomes in opposing fashions: negatively by limiting virus replication and/or spread, or positively by inducing antitumor immune responses. Many aspects of the OV-tumor/host interaction are important in delineating the effectiveness of therapy: (i) innate immune responses and the degree of inflammation induced; (ii) types of virus-induced cell death; (iii) inherent tumor physiology, such as infiltrating and resident immune cells, vascularity/hypoxia, lymphatics, and stromal architecture; and (iv) tumor cell phenotype, including alterations in IFN signaling, oncogenic pathways, cell surface immune markers [MHC, costimulatory, and natural killer (NK) receptors], and the expression of immunosuppressive factors. Recent clinical trials with a variety of OVs, especially those expressing granulocyte macrophage colony-stimulating factor (GM-CSF), have demonstrated efficacy and induction of antitumor immune responses in the absence of significant toxicity. Manipulating the balance between antivirus and antitumor responses, often involving overlapping immune pathways, will be critical to the clinical success of OVs.

  11. Implications of MicroRNAs in Oncolytic Virotherapy

    Directory of Open Access Journals (Sweden)

    Xavier Bofill-De Ros

    2017-07-01

    Full Text Available MicroRNAs (miRNAs are an abundant class of small non-coding RNA molecules (~22 nt that can repress gene expression. Deregulation of certain miRNAs is widely recognized as a robust biomarker for many neoplasms, as well as an important player in tumorigenesis and the establishment of tumoral microenvironments. The downregulation of specific miRNAs in tumors has been exploited as a mechanism to provide selectivity to oncolytic viruses or gene-based therapies. miRNA response elements recognizing miRNAs expressed in specific tissues, but downregulated in tumors, have been inserted into the 3′UTR of viral genes to promote the degradation of these viral mRNAs in healthy tissue, but not in tumor cells. Consequently, oncolytic virotherapy-associated toxicities were diminished, while therapeutic activity in tumor cells was preserved. However, viral infections themselves can modulate the miRNome of the host cell, and such miRNA changes under infection impact the normal viral lifecycle. Thus, there is a miRNA-mediated interplay between virus and host cell, affecting both viral and cellular activities. Moreover, the outcome of such interactions may be cell type or condition specific, suggesting that the impact on normal and tumoral cells may differ. Here, we provide an insight into the latest developments in miRNA-based viral engineering for cancer therapy, following the most recent discoveries in miRNA biology. Furthermore, we report on the relevance of miRNAs in virus–host cell interaction, and how such knowledge can be exploited to improve the control of viral activity in tumor cells.

  12. Stem Cell-Based Cell Carrier for Targeted Oncolytic Virotherapy: Translational Opportunity and Open Questions

    Directory of Open Access Journals (Sweden)

    Janice Kim

    2015-11-01

    Full Text Available Oncolytic virotherapy for cancer is an innovative therapeutic option where the ability of a virus to promote cell lysis is harnessed and reprogrammed to selectively destroy cancer cells. Such treatment modalities exhibited antitumor activity in preclinical and clinical settings and appear to be well tolerated when tested in clinical trials. However, the clinical success of oncolytic virotherapy has been significantly hampered due to the inability to target systematic metastasis. This is partly due to the inability of the therapeutic virus to survive in the patient circulation, in order to target tumors at distant sites. An early study from various laboratories demonstrated that cells infected with oncolytic virus can protect the therapeutic payload form the host immune system as well as function as factories for virus production and enhance the therapeutic efficacy of oncolytic virus. While a variety of cell lineages possessed potential as cell carriers, copious investigation has established stem cells as a very attractive cell carrier system in oncolytic virotherapy. The ideal cell carrier desire to be susceptible to viral infection as well as support viral infection, maintain immunosuppressive properties to shield the loaded viruses from the host immune system, and most importantly possess an intrinsic tumor homing ability to deliver loaded viruses directly to the site of the metastasis—all qualities stem cells exhibit. In this review, we summarize the recent work in the development of stem cell-based carrier for oncolytic virotherapy, discuss the advantages and disadvantages of a variety of cell carriers, especially focusing on why stem cells have emerged as the leading candidate, and finally propose a future direction for stem cell-based targeted oncolytic virotherapy that involves its establishment as a viable treatment option for cancer patients in the clinical setting.

  13. Cytokine-modified VSV is attenuated for neural pathology, but is both highly immunogenic and oncolytic

    OpenAIRE

    Miller, James; Bidula, Sarah M; Jensen, Troels M; Reiss, Carol Shoshkes

    2009-01-01

    Vesicular stomatitis virus (VSV), an enveloped, nonsegmented, negative-stranded RNA virus, is being tested by several laboratories as an antitumor agent. Unfortunately, viral infection of the central nervous system (CNS) has been observed by many groups following administration to tumor-bearing animals. In rodents, VSV encephalitis is characterized by weight-loss, paralysis, and high mortality. In order to provide protection from VSV infection of the CNS after therapeutic administration, we h...

  14. Flip-Flop HSV-BAC: bacterial artificial chromosome based system for rapid generation of recombinant herpes simplex virus vectors using two independent site-specific recombinases

    Directory of Open Access Journals (Sweden)

    Todo Tomoki

    2006-09-01

    Full Text Available Abstract Background Oncolytic herpes simplex virus (HSV vectors that specifically replicate in and kill tumor cells sparing normal cells are a promising cancer therapy. Traditionally, recombinant HSV vectors have been generated through homologous recombination between the HSV genome and a recombination plasmid, which usually requires laborious screening or selection and can take several months. Recent advances in bacterial artificial chromosome (BAC technology have enabled cloning of the whole HSV genome as a BAC plasmid and subsequent manipulation in E. coli. Thus, we sought a method to generate recombinant oncolytic HSV vectors more easily and quickly using BAC technology. Results We have developed an HSV-BAC system, termed the Flip-Flop HSV-BAC system, for the rapid generation of oncolytic HSV vectors. This system has the following features: (i two site-specific recombinases, Cre and FLPe, are used sequentially to integrate desired sequences and to excise the BAC sequences, respectively; and (ii the size of the HSV-BAC-insert genome exceeds the packaging limit of HSV so only correctly recombined virus grows efficiently. We applied this to the construction of an HSV-BAC plasmid that can be used for the generation of transcriptionally-targeted HSV vectors. BAC sequences were recombined into the UL39 gene of HSV ICP4-deletion mutant d120 to generate M24-BAC virus, from which HSV-BAC plasmid pM24-BAC was isolated. An ICP4 expression cassette driven by an exogenous promoter was re-introduced to pM24-BAC by Cre-mediated recombination and nearly pure preparations of recombinant virus were obtained typically in two weeks. Insertion of the ICP4 coding sequence alone did not restore viral replication and was only minimally better than an ICP4-null construct, whereas insertion of a CMVIE promoter-ICP4 transgene (bM24-CMV efficiently drove viral replication. The levels of bM24-CMV replication in tumor cells varied considerably compared to hrR3 (UL39

  15. Vesicular stomatitis virus as an oncolytic agent against pancreatic ductal adenocarcinoma.

    Science.gov (United States)

    Murphy, Andrea M; Besmer, Dahlia M; Moerdyk-Schauwecker, Megan; Moestl, Natascha; Ornelles, David A; Mukherjee, Pinku; Grdzelishvili, Valery Z

    2012-03-01

    Vesicular stomatitis virus (VSV) is a promising oncolytic agent against a variety of cancers. However, it has never been tested in any pancreatic cancer model. Pancreatic ductal adenocarcinoma (PDA) is the most common and aggressive form of pancreatic cancer. In this study, the oncolytic potentials of several VSV variants were analyzed in a panel of 13 clinically relevant human PDA cell lines and compared to conditionally replicative adenoviruses (CRAds), Sendai virus and respiratory syncytial virus. VSV variants showed oncolytic abilities superior to those of other viruses, and some cell lines that exhibited resistance to other viruses were successfully killed by VSV. However, PDA cells were highly heterogeneous in their susceptibility to virus-induced oncolysis, and several cell lines were resistant to all tested viruses. Resistant cells showed low levels of very early VSV RNA synthesis, indicating possible defects at initial stages of infection. In addition, unlike permissive PDA cell lines, most of the resistant cell lines were able to both produce and respond to interferon, suggesting that intact type I interferon responses contributed to their resistance phenotype. Four cell lines that varied in their permissiveness to VSV-ΔM51 and CRAd dl1520 were tested in mice, and the in vivo results closely mimicked those in vitro. While our results demonstrate that VSV is a promising oncolytic agent against PDA, further studies are needed to better understand the molecular mechanisms of resistance of some PDAs to oncolytic virotherapy.

  16. Chemotherapy and Oncolytic Virotherapy: Advanced Tactics in the War against Cancer

    Directory of Open Access Journals (Sweden)

    Andrew eNguyen

    2014-06-01

    Full Text Available Cancer is a traitorous archenemy that threatens our survival. Its ability to evade detection and adapt to various cancer therapies means that it is a moving target that becomes increasingly difficult to attack. Through technological advancements we have developed sophisticated weapons to fight off tumor growth and invasion. However, if we are to stand a chance in this war against cancer, advanced tactics will be required to maximize the use of our available resources. Oncolytic viruses are multi-functional cancer-fighters that can be engineered to suit many different strategies; in particular, their retooling can facilitate increased capacity for direct tumor killing (oncolytic virotherapy and elicit adaptive antitumor immune responses (oncolytic immunotherapy. However, administration of these modified oncolytic viruses alone, rarely induces successful regression of established tumors. This may be attributed to host antiviral immunity that acts to eliminate viral particles, as well as the capacity for tumors to adapt to therapeutic selective pressure. It has been shown that various chemotherapeutic drugs with distinct functional properties can potentiate the antitumor efficacy of oncolytic viruses. In this review, we summarize the chemotherapeutic combinatorial strategies used to optimize virally-induced destruction of tumors. With a particular focus on pharmaceutical immunomodulators, we discuss how specific therapeutic contexts may alter the effects of these synergistic combinations and their implications for future clinical use.

  17. Targeting Nucleotide Biosynthesis: A Strategy for Improving the Oncolytic Potential of DNA Viruses.

    Science.gov (United States)

    Irwin, Chad R; Hitt, Mary M; Evans, David H

    2017-01-01

    The rapid growth of tumors depends upon elevated levels of dNTPs, and while dNTP concentrations are tightly regulated in normal cells, this control is often lost in transformed cells. This feature of cancer cells has been used to advantage to develop oncolytic DNA viruses. DNA viruses employ many different mechanisms to increase dNTP levels in infected cells, because the low concentration of dNTPs found in non-cycling cells can inhibit virus replication. By disrupting the virus-encoded gene(s) that normally promote dNTP biosynthesis, one can assemble oncolytic versions of these agents that replicate selectively in cancer cells. This review covers the pathways involved in dNTP production, how they are dysregulated in cancer cells, and the various approaches that have been used to exploit this biology to improve the tumor specificity of oncolytic viruses. In particular, we compare and contrast the ways that the different types of oncolytic virus candidates can directly modulate these processes. We limit our review to the large DNA viruses that naturally encode homologs of the cellular enzymes that catalyze dNTP biogenesis. Lastly, we consider how this knowledge might guide future development of oncolytic viruses.

  18. Targeting Nucleotide Biosynthesis: A Strategy for Improving the Oncolytic Potential of DNA Viruses

    Directory of Open Access Journals (Sweden)

    Chad R. Irwin

    2017-09-01

    Full Text Available The rapid growth of tumors depends upon elevated levels of dNTPs, and while dNTP concentrations are tightly regulated in normal cells, this control is often lost in transformed cells. This feature of cancer cells has been used to advantage to develop oncolytic DNA viruses. DNA viruses employ many different mechanisms to increase dNTP levels in infected cells, because the low concentration of dNTPs found in non-cycling cells can inhibit virus replication. By disrupting the virus-encoded gene(s that normally promote dNTP biosynthesis, one can assemble oncolytic versions of these agents that replicate selectively in cancer cells. This review covers the pathways involved in dNTP production, how they are dysregulated in cancer cells, and the various approaches that have been used to exploit this biology to improve the tumor specificity of oncolytic viruses. In particular, we compare and contrast the ways that the different types of oncolytic virus candidates can directly modulate these processes. We limit our review to the large DNA viruses that naturally encode homologs of the cellular enzymes that catalyze dNTP biogenesis. Lastly, we consider how this knowledge might guide future development of oncolytic viruses.

  19. Antiglioma oncolytic virotherapy: unattainable goal or a success story in the making?

    Science.gov (United States)

    Dey, Mahua; Auffinger, Brenda; Lesniak, Maciej S; Ahmed, Atique U

    2014-01-01

    Initial observations from as early as the mid-1800s suggested that patients suffering from hematological malignancies would transiently go into remission upon naturally contracting viral infections laid the foundation for the oncolytic virotherapy research field. Since then, research focusing on anticancer oncolytic virotherapy has rapidly evolved. Today, oncolytic viral vectors have been engineered to stimulate and manipulate the host immune system, selectively targeting tumor tissues while sparing non-neoplastic cells. Glioblastoma multiforme, the most common adult primary brain tumor, has a disasterous history. It is one of the most deadly cancers known to humankind. Over the last century our understanding of this disease has grown exponentially. However, the median survival of patients suffering from this disease has only been extended by a few months. Even with the best, most aggressive modern therapeutic approaches available, malignant gliomas are still virtually 100% fatal. Motivated by the desperate need to find effective treatment strategies, more investments have been applied to oncolytic virotherapy preclinical and clinical studies. In this review we will discuss the antiglioma oncolytic virotherapy research field. We will survey its history and the principles laid down to serve as basis for preclinical works. We will also debate the variety of viral vectors used, their clinical applications, the lessons learned from clinical trials and possible future directions. PMID:24910708

  20. Productive homologous and non-homologous recombination of hepatitis C virus in cell culture

    DEFF Research Database (Denmark)

    Scheel, Troels K H; Galli, Andrea; Li, Yi-Ping

    2013-01-01

    -genotypic recombination could occur, but at a lower frequency than intra-genotypic recombination. Productive recombination of attenuated HCV genomes depended on expression of all HCV proteins and tolerated duplicated sequence. In general, no strong site specificity was observed. Non-homologous recombination was observed...

  1. Oncolytic viruses against cancer stem cells: A promising approach for gastrointestinal cancer.

    Science.gov (United States)

    Huang, Fang; Wang, Bin-Rong; Wu, Ye-Qing; Wang, Fan-Chao; Zhang, Jian; Wang, Yi-Gang

    2016-09-21

    Gastrointestinal cancer has been one of the five most commonly diagnosed and leading causes of cancer mortality over the past few decades. Great progress in traditional therapies has been made, which prolonged survival in patients with early cancer, yet tumor relapse and drug resistance still occurred, which is explained by the cancer stem cell (CSC) theory. Oncolytic virotherapy has attracted increasing interest in cancer because of its ability to infect and lyse CSCs. This paper reviews the basic knowledge, CSC markers and therapeutics of gastrointestinal cancer (liver, gastric, colon and pancreatic cancer), as well as research advances and possible molecular mechanisms of various oncolytic viruses against gastrointestinal CSCs. This paper also summarizes the existing obstacles to oncolytic virotherapy and proposes several alternative suggestions to overcome the therapeutic limitations.

  2. Oncolytic virotherapy using herpes simplex virus: how far have we come?

    Directory of Open Access Journals (Sweden)

    Sokolowski NAS

    2015-11-01

    Full Text Available Nicolas AS Sokolowski,1 Helen Rizos,2 Russell J Diefenbach1 1Centre for Virus Research, Westmead Millennium Institute for Medical Research, The University of Sydney, 2Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Macquarie University, NSW, Australia Abstract: Oncolytic virotherapy exploits the properties of human viruses to naturally cause cytolysis of cancer cells. The human pathogen herpes simplex virus (HSV has proven particularly amenable for use in oncolytic virotherapy. The relative safety of HSV coupled with extensive knowledge on how HSV interacts with the host has provided a platform for manipulating HSV to enhance the targeting and killing of human cancer cells. This has culminated in the approval of talimogene laherparepvec for the treatment of melanoma. This review focuses on the development of HSV as an oncolytic virus and where the field is likely to head in the future. Keywords: herpes simplex virus, cancer, immunity, combination therapy, oncolysis

  3. Ultrasound-mediated oncolytic virus delivery and uptake for increased therapeutic efficacy: state of art

    Directory of Open Access Journals (Sweden)

    Nande R

    2015-11-01

    Full Text Available Rounak Nande,1 Candace M Howard,2 Pier Paolo Claudio,3,4 1Department of Biochemistry and Microbiology, Marshall University School of Medicine, Huntington, WV, 2Department of Radiology, University of Mississippi Medical Center, Jackson, MS, 3Department of BioMolecular Sciences and National Center for Natural Products Research, School of Pharmacy, University of Mississippi, MS, 4Department of Radiation Oncology, University of Mississippi Medical Center, Jackson, MS, USA Abstract: The field of ultrasound (US has changed significantly from medical imaging and diagnosis to treatment strategies. US contrast agents or microbubbles (MB are currently being used as potential carriers for chemodrugs, small molecules, nucleic acids, small interfering ribonucleic acid, proteins, adenoviruses, and oncolytic viruses. Oncolytic viruses can selectively replicate within and destroy a cancer cell, thus making them a powerful therapeutic in treating late-stage or metastatic cancer. These viruses have been shown to have robust activity in clinical trials when injected directly into tumor nodules. However limitations in oncolytic virus’ effectiveness and its delivery approach have warranted exploration of ultrasound-mediated delivery. Gene therapy bearing adenoviruses or oncolytic viruses can be coupled with MBs and injected intravenously. Following application of US energy to the target region, the MBs cavitate, and the resulting shock wave enhances drug, gene, or adenovirus uptake. Though the underlying mechanism is yet to be fully understood, there is evidence to suggest that mechanical pore formation of cellular membranes allows for the temporary uptake of drugs. This delivery method circumvents the limitations due to stimulation of the immune system that prevented intravenous administration of viruses. This review provides insight into this intriguing new frontier on the delivery of oncolytic viruses to tumor sites.Keywords: microbubbles, ultrasound

  4. Evidence for Oncolytic Virotherapy: Where Have We Got to and Where Are We Going?

    Directory of Open Access Journals (Sweden)

    Samantha Turnbull

    2015-12-01

    Full Text Available The last few years have seen an increased interest in immunotherapy in the treatment of malignant disease. In particular, there has been significant enthusiasm for oncolytic virotherapy, with a large amount of pre-clinical data showing promise in animal models in a wide range of tumour types. How do we move forward into the clinical setting and translate something which has such potential into meaningful clinical outcomes? Here, we review how the field of oncolytic virotherapy has developed thus far and what the future may hold.

  5. Oncolytic Viruses—Natural and Genetically Engineered Cancer Immunotherapies

    Directory of Open Access Journals (Sweden)

    Sachin R. Jhawar

    2017-09-01

    Full Text Available There has long been interest in innovating an approach by which tumor cells can be selectively and specifically targeted and destroyed. The discovery of viruses that lyse tumor cells, termed oncolytic viruses (OVs, has led to a revolution in the treatment of cancer. The potential of OVs to improve the therapeutic ratio is derived from their ability to preferentially infect and replicate in cancer cells while avoiding destruction of normal cells surrounding the tumor. Two main mechanisms exist through which these viruses are reported to improve outcomes: direct lysis of tumor cells and indirect augmentation of host anti-tumor immunity. With these factors in mind, viruses are chosen or modified to selectively target tumor cells, decrease pathogenicity to normal cells, decrease the antiviral immune response (to prevent viral clearance, and increase the antitumor immune response. While only one OV has been approved for the treatment of cancer in the United States, and only two other OVs have been approved worldwide, a wide spectrum of OVs are in various stages of preclinical development and in clinical trials. These viruses are being studied as alternatives and adjuncts to more traditional cancer therapies including surgical resection, chemotherapy, radiation, hormonal therapies, targeted therapies, and other immunotherapies. Here, we review the natural characteristics and genetically engineered modifications that enhance the effectiveness of OVs for the treatment of cancer.

  6. Memory versus effector immune responses in oncolytic virotherapies.

    Science.gov (United States)

    Macnamara, Cicely; Eftimie, Raluca

    2015-07-21

    The main priority when designing cancer immuno-therapies has been to seek viable biological mechanisms that lead to permanent cancer eradication or cancer control. Understanding the delicate balance between the role of effector and memory cells on eliminating cancer cells remains an elusive problem in immunology. Here we make an initial investigation into this problem with the help of a mathematical model for oncolytic virotherapy; although the model can in fact be made general enough to be applied also to other immunological problems. According to this model, we find that long-term cancer control is associated with a large number of persistent effector cells (irrespective of the initial peak in effector cell numbers). However, this large number of persistent effector cells is sustained by a relatively large number of memory cells. Moreover, the results of the mathematical model suggest that cancer control from a dormant state cannot be predicted by the size of the memory population. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Pediatric glioma stem cells: biologic strategies for oncolytic HSV virotherapy.

    Science.gov (United States)

    Friedman, Gregory K; Raborn, Joel; Kelly, Virginia M; Cassady, Kevin A; Markert, James M; Gillespie, G Yancey

    2013-01-01

    While glioblastoma multiforme (GBM) is the most common adult malignant brain tumor, GBMs in childhood represent less than 10% of pediatric malignant brain tumors and are phenotypically and molecularly distinct from adult GBMs. Similar to adult patients, outcomes for children with high-grade gliomas (HGGs) remain poor. Furthermore, the significant morbidity and mortality yielded by pediatric GBM is compounded by neurotoxicity for the developing brain caused by current therapies. Poor outcomes have been attributed to a subpopulation of chemotherapy and radiotherapy resistant cells, termed "glioma stem cells" (GSCs), "glioma progenitor cells," or "glioma-initiating cells," which have the ability to initiate and maintain the tumor and to repopulate the recurring tumor after conventional therapy. Future innovative therapies for pediatric HGG must be able to eradicate these therapy-resistant GSCs. Oncolytic herpes simplex viruses (oHSV), genetically engineered to be safe for normal cells and to express diverse foreign anti-tumor therapeutic genes, have been demonstrated in preclinical studies to infect and kill GSCs and tumor cells equally while sparing normal brain cells. In this review, we discuss the unique aspects of pediatric GSCs, including markers to identify them, the microenvironment they reside in, signaling pathways that regulate them, mechanisms of cellular resistance, and approaches to target GSCs, with a focus on the promising therapeutic, genetically engineered oHSV.

  8. Talimogene Laherparepvec: An Oncolytic Virus Therapy for Melanoma.

    Science.gov (United States)

    Corrigan, Patricia A; Beaulieu, Caroline; Patel, Rashmi B; Lowe, Denise K

    2017-08-01

    To review the efficacy and safety of talimogene laherparepvec (T-VEC) as well as its pharmacology, pharmacokinetics, drug-drug interactions, handling procedures, cost considerations, and place in therapy. Searches of PubMed (1966 to February 2017) and Cochrane Library (1999 to February 2017) were conducted using the terms talimogene laherparepvec, T-VEC, OncoVEX, immunotherapy, melanoma, and oncolytic virus. Additional information was determined from bibliographies, manufacturer product labeling and website, meeting abstracts, Food and Drug Administration website, and clinicaltrials.gov. A total of 79 English-language publications were identified. Articles that assessed T-VEC's pharmacokinetics, pharmacodynamics, mechanism, dosing, safety, and efficacy were included as well as narrative reviews that provided practical information. Clinical trials have confirmed the safety and efficacy of T-VEC as monotherapy for the treatment of advanced melanoma, with an overall response rate (ORR) of 26%. Relative to granulocyte-macrophage colony-stimulating factor, T-VEC significantly increased durable response rate (DRR; 16.3% vs 2.1%, P melanoma recurrent after initial surgery. T-VEC improves ORR and DRR as a single agent, shows promise in combination therapy, and is well tolerated. Ongoing trials will determine if T-VEC has a role in early treatment or in combination therapy for melanoma or other malignancies.

  9. Oncolytic Virotherapy: A Contest between Apples and Oranges.

    Science.gov (United States)

    Russell, Stephen J; Peng, Kah-Whye

    2017-05-03

    Viruses can be engineered or adapted for selective propagation in neoplastic tissues and further modified for therapeutic transgene expression to enhance their antitumor potency and druggability. Oncolytic viruses (OVs) can be administered locally or intravenously and spread to a variable degree at sites of tumor growth. OV-infected tumor cells die in situ, releasing viral and tumor antigens that are phagocytosed by macrophages, transported to regional lymph nodes, and presented to antigen-reactive T cells, which proliferate before dispersing to kill uninfected tumor cells at distant sites. Several OVs are showing clinical promise, and one of them, talimogene laherparepvec (T-VEC), was recently granted marketing approval for intratumoral therapy of nonresectable metastatic melanoma. T-VEC also appears to substantially enhance clinical responsiveness to checkpoint inhibitor antibody therapy. Here, we examine the T-VEC paradigm and review some of the approaches currently being pursued to develop the next generation of OVs for both local and systemic administration, as well as for use in combination with other immunomodulatory agents. Copyright © 2017 The American Society of Gene and Cell Therapy. Published by Elsevier Inc. All rights reserved.

  10. Moving oncolytic viruses into the clinic: clinical-grade production, purification, and characterization of diverse oncolytic viruses

    Directory of Open Access Journals (Sweden)

    Guy Ungerechts

    2016-01-01

    Full Text Available Oncolytic viruses (OVs are unique anticancer agents based on their pleotropic modes of action, which include, besides viral tumor cell lysis, activation of antitumor immunity. A panel of diverse viruses, often genetically engineered, has advanced to clinical investigation, including phase 3 studies. This diversity of virotherapeutics not only offers interesting opportunities for the implementation of different therapeutic regimens but also poses challenges for clinical translation. Thus, manufacturing processes and regulatory approval paths need to be established for each OV individually. This review provides an overview of clinical-grade manufacturing procedures for OVs using six virus families as examples, and key challenges are discussed individually. For example, different virus features with respect to particle size, presence/absence of an envelope, and host species imply specific requirements for measures to ensure sterility, for handling, and for determination of appropriate animal models for toxicity testing, respectively. On the other hand, optimization of serum-free culture conditions, increasing virus yields, development of scalable purification strategies, and formulations guaranteeing long-term stability are challenges common to several if not all OVs. In light of the recent marketing approval of the first OV in the Western world, strategies for further upscaling OV manufacturing and optimizing product characterization will receive increasing attention.

  11. Effect of Repeat Dosing of Engineered Oncolytic Herpes Simplex Virus on Preclinical Models of Rhabdomyosarcoma

    Directory of Open Access Journals (Sweden)

    Alicia M. Waters

    2016-10-01

    Full Text Available Rhabdomyosarcoma (RMS, a tumor of skeletal muscle origin, is the most common sarcoma of childhood. Despite multidrug chemotherapy regimens, surgical intervention, and radiation treatment, outcomes remain poor, especially in advanced disease, and novel therapies are needed for the treatment of these aggressive malignancies. Genetically engineered oncolytic viruses, such as herpes simplex virus-1 (HSV, are currently being explored as treatments for pediatric tumors. M002, an oncolytic HSV, has both copies of the γ134.5 gene deleted, enabling replication in tumor cells but thwarting infection of normal, postmitotic cells. We hypothesized that M002 would infect human RMS tumor cells and lead to decreased tumor cell survival in vitro and impede tumor growth in vivo. In the current study, we demonstrated that M002 could infect, replicate in, and decrease cell survival in both embryonal (ERMS and alveolar rhabdomyosarcoma (ARMS cells. Additionally, M002 reduced xenograft tumor growth and increased animal survival in both ARMS and ERMS. Most importantly, we showed for the first time that repeated dosing of oncolytic virus coupled with low-dose radiation provided improved tumor response in RMS. These findings provide support for the clinical investigation of oncolytic HSV in pediatric RMS.

  12. Pediatric cancer gone viral. Part I: strategies for utilizing oncolytic herpes simplex virus-1 in children

    Science.gov (United States)

    Cripe, Timothy P; Chen, Chun-Yu; Denton, Nicholas L; Haworth, Kellie B; Hutzen, Brian; Leddon, Jennifer L; Streby, Keri A; Wang, Pin-Yi; Markert, James M; Waters, Alicia M; Gillespie, George Yancey; Beierle, Elizabeth A; Friedman, Gregory K

    2015-01-01

    Progress for improving outcomes in pediatric patients with solid tumors remains slow. In addition, currently available therapies are fraught with numerous side effects, often causing significant life-long morbidity for long-term survivors. The use of viruses to kill tumor cells based on their increased vulnerability to infection is gaining traction, with several viruses moving through early and advanced phase clinical testing. The prospect of increased efficacy and decreased toxicity with these agents is thus attractive for pediatric cancer. In part I of this two-part review, we focus on strategies for utilizing oncolytic engineered herpes simplex virus (HSV) to target pediatric malignancies. We discuss mechanisms of action, routes of delivery, and the role of preexisting immunity on antitumor efficacy. Challenges to maximizing oncolytic HSV in children are examined, and we highlight how these may be overcome through various arming strategies. We review the preclinical and clinical evidence demonstrating safety of a variety of oncolytic HSVs. In Part II, we focus on the antitumor efficacy of oncolytic HSV in pediatric tumor types, pediatric clinical advances made to date, and future prospects for utilizing HSV in pediatric patients with solid tumors. PMID:26436135

  13. Pediatric cancer gone viral. Part I: strategies for utilizing oncolytic herpes simplex virus-1 in children

    Directory of Open Access Journals (Sweden)

    Timothy P Cripe

    Full Text Available Progress for improving outcomes in pediatric patients with solid tumors remains slow. In addition, currently available therapies are fraught with numerous side effects, often causing significant life-long morbidity for long-term survivors. The use of viruses to kill tumor cells based on their increased vulnerability to infection is gaining traction, with several viruses moving through early and advanced phase clinical testing. The prospect of increased efficacy and decreased toxicity with these agents is thus attractive for pediatric cancer. In part I of this two-part review, we focus on strategies for utilizing oncolytic engineered herpes simplex virus (HSV to target pediatric malignancies. We discuss mechanisms of action, routes of delivery, and the role of preexisting immunity on antitumor efficacy. Challenges to maximizing oncolytic HSV in children are examined, and we highlight how these may be overcome through various arming strategies. We review the preclinical and clinical evidence demonstrating safety of a variety of oncolytic HSVs. In Part II, we focus on the antitumor efficacy of oncolytic HSV in pediatric tumor types, pediatric clinical advances made to date, and future prospects for utilizing HSV in pediatric patients with solid tumors.

  14. 77 FR 22333 - Prospective Grant of Exclusive License: Development of Oncolytic Viral Cancer Therapies

    Science.gov (United States)

    2012-04-13

    ... Oncolytic Viral Cancer Therapies AGENCY: National Institutes of Health, Public Health Service, HHS. ACTION... gene is expressed. For example, the foreign DNA can be related to a viral pathogen, tumor- associated... subject, the foreign gene is expressed in vivo to elicit an immune response or express the therapeutic...

  15. Oncolytic viral purging of leukemic hematopoietic stem and progenitor cells with Myxoma virus.

    Science.gov (United States)

    Rahman, Masmudur M; Madlambayan, Gerard J; Cogle, Christopher R; McFadden, Grant

    2010-01-01

    High-dose chemotherapy and radiation followed by autologous blood and marrow transplantation (ABMT) has been used for the treatment of certain cancers that are refractory to standard therapeutic regimes. However, a major challenge with ABMT for patients with hematologic malignancies is disease relapse, mainly due to either contamination with cancerous hematopoietic stem and progenitor cells (HSPCs) within the autograft or the persistence of residual therapy-resistant disease niches within the patient. Oncolytic viruses represent a promising therapeutic approach to prevent cancer relapse by eliminating tumor-initiating cells that contaminate the autograft. Here we summarize an ex vivo "purging" strategy with oncolytic Myxoma virus (MYXV) to remove cancer-initiating cells from patient autografts prior to transplantation. MYXV, a novel oncolytic poxvirus with potent anti-cancer properties in a variety of in vivo tumor models, can specifically eliminate cancerous stem and progenitor cells from samples obtained from acute myelogenous leukemia (AML) patients, while sparing normal CD34+ hematopoietic stem and progenitor cells capable of rescuing hematopoiesis following high dose conditioning. We propose that a broader subset of patients with intractable hematologic malignancies who have failed standard therapy could become eligible for ABMT when the treatment schema is coupled with ex vivo oncolytic therapy. 2010 Elsevier Ltd. All rights reserved.

  16. The ex vivo purge of cancer cells using oncolytic viruses: recent advances and clinical implications

    Directory of Open Access Journals (Sweden)

    Tsang JJ

    2015-01-01

    Full Text Available Jovian J Tsang,1,2 Harold L Atkins2,3 1Department of Biochemistry, University of Ottawa, 2Cancer Therapeutics, Ottawa Hospital Research Institute, 3Blood and Marrow Transplant Program, The Ottawa Hospital, Ottawa, ON, Canada Abstract: Hematological malignancies are treated with intensive high-dose chemotherapy, with or without radiation. This is followed by hematopoietic stem cell (HSC transplantation (HSCT to rescue or reconstitute hematopoiesis damaged by the anticancer therapy. Autologous HSC grafts may contain cancer cells and purging could further improve treatment outcomes. Similarly, allogeneic HSCT may be improved by selectively purging alloreactive effector cells from the graft rather than wholesale immune cell depletion. Viral agents that selectively replicate in specific cell populations are being studied in experimental models of cancer and immunological diseases and have potential applications in the context of HSC graft engineering. This review describes preclinical studies involving oncolytic virus strains of adenovirus, herpes simplex virus type 1, myxoma virus, and reovirus as ex vivo purging agents for HSC grafts, as well as in vitro and in vivo experimental studies using oncolytic coxsackievirus, measles virus, parvovirus, vaccinia virus, and vesicular stomatitis virus to eradicate hematopoietic malignancies. Alternative ex vivo oncolytic virus strategies are also outlined that aim to reduce the risk of relapse following autologous HSCT and mitigate morbidity and mortality due to graft-versus-host disease in allogeneic HSCT. Keywords: hematopoietic stem cells, oncolytic virus, hematopoietic stem cell transplantation, stem cell graft purging, hematopoietic malignancy, graft vs host disease

  17. Oncolytic virotherapy as emerging immunotherapeutic modality: potential of parvovirus H-1

    Directory of Open Access Journals (Sweden)

    Markus eMoehler

    2014-05-01

    Full Text Available Human tumors develop multiple strategies to evade recognition and efficient suppression by the immune system. Therefore, a variety of immunotherapeutic strategies have been developed to reactivate and reorganize the human immune system. The recent development of new antibodies against immune check points may help to overcome the immune silencing induced by human tumors. Some of these antibodies have already been approved for treatment of various solid tumor entities. Interestingly, targeting antibodies may be combined with standard chemotherapy or radiation protocols. Furthermore, recent evidence indicates that intratumoral (it or intravenous (iv injections of replicative oncolytic viruses such as herpes simplex-, pox-, parvo- or adenoviruses may also reactivate the human immune system. By generating tumor cell lysates in situ, oncolytic viruses overcome cellular tumor resistance mechanisms and induce immunogenic tumor cell death resulting in the recognition of newly released tumor antigens.This is in particular the case of the oncolytic parvovirus H-1 (H-1PV which is able to kill human tumor cells and stimulate an antitumor immune response through increased presentation of tumor-associated antigens, maturation of dendritic cells and release of proinflammatory cytokines. Current research and clinical studies aim to assess the potential of oncolytic virotherapy and its combination with immunotherapeutic agents or conventional treatments to further induce effective antitumoral immune responses.

  18. Oncolytic virotherapy as emerging immunotherapeutic modality: potential of parvovirus h-1.

    Science.gov (United States)

    Moehler, Markus; Goepfert, Katrin; Heinrich, Bernd; Breitbach, Caroline J; Delic, Maike; Galle, Peter Robert; Rommelaere, Jean

    2014-01-01

    Human tumors develop multiple strategies to evade recognition and efficient suppression by the immune system. Therefore, a variety of immunotherapeutic strategies have been developed to reactivate and reorganize the human immune system. The recent development of new antibodies against immune check points may help to overcome the immune silencing induced by human tumors. Some of these antibodies have already been approved for treatment of various solid tumor entities. Interestingly, targeting antibodies may be combined with standard chemotherapy or radiation protocols. Furthermore, recent evidence indicates that intratumoral or intravenous injections of replicative oncolytic viruses such as herpes simplex-, pox-, parvo-, or adenoviruses may also reactivate the human immune system. By generating tumor cell lysates in situ, oncolytic viruses overcome cellular tumor resistance mechanisms and induce immunogenic tumor cell death resulting in the recognition of newly released tumor antigens. This is in particular the case of the oncolytic parvovirus H-1 (H-1PV), which is able to kill human tumor cells and stimulate an anti-tumor immune response through increased presentation of tumor-associated antigens, maturation of dendritic cells, and release of pro-inflammatory cytokines. Current research and clinical studies aim to assess the potential of oncolytic virotherapy and its combination with immunotherapeutic agents or conventional treatments to further induce effective antitumoral immune responses.

  19. Comparison of Liver Detargeting Strategies for Systemic Therapy with Oncolytic Adenovirus Serotype 5

    Directory of Open Access Journals (Sweden)

    Tien V. Nguyen

    2017-08-01

    Full Text Available Oncolytic viruses would ideally be of use for systemic therapy to treat disseminated cancer. To do this safely, this may require multiple layers of cancer specificity. The pharmacology and specificity of oncolytic adenoviruses can be modified by (1 physical retargeting, (2 physical detargeting, (3 chemical shielding, or (4 by modifying the ability of viral early gene products to selectively activate in cancer versus normal cells. We explored the utility of these approaches with oncolytic adenovirus serotype 5 (Ad5 in immunocompetent Syrian hamsters bearing subcutaneous HaK tumors. After a single intravenous injection to reach the distant tumors, the physically hepatocyte-detargeted virus Ad5-hexon-BAP was more effective than conditionally replicating Ad5-dl1101/07 with mutations in its E1A protein. When these control or Ad5 treated animals were treated a second time by intratumoral injection, prior exposure to Ad5 did not affect tumor growth, suggesting that anti-Ad immunity neither prevented treatment nor amplified anti-tumor immune responses. Ad5-dl1101/07 was next chemically shielded with polyethylene glycol (PEG. While 5 kDa of PEG blunted pro-inflammatory IL-6 production induced by Ad5-dl1101/07, this shielding reduced Ad oncolytic activity.

  20. Evaluation of attenuation, immunogenicity and efficacy of a bovine parainfluenza virus type 3 (PIV-3) vaccine and a recombinant chimeric bovine/human PIV-3 vaccine vector in rhesus monkeys.

    Science.gov (United States)

    Pennathur, Sridhar; Haller, Aurelia A; MacPhail, Mia; Rizzi, Tom; Kaderi, Sepideh; Fernandes, Fiona; Bicha, Leenas; Schickli, Jeanne H; Tang, Roderick S; Chen, Wendy; Nguyen, Nick; Mathie, Sharon; Mehta, Hersh; Coelingh, Kathleen L

    2003-12-01

    Restricted replication in the respiratory tract of rhesus monkeys is an intrinsic property of bovine parainfluenza virus type 3 (bPIV-3) strains. This host range phenotype of bPIV-3 has been utilized as a marker to evaluate the attenuation of bPIV-3 vaccines for human use. Two safety, immunogenicity and efficacy studies in primates evaluated and compared three human parainfluenza virus type 3 (hPIV-3) vaccine candidates: biologically derived bPIV-3, a plasmid-derived bPIV-3 (r-bPIV-3) and a chimeric bovine/human PIV-3 (b/hPIV-3). These studies also examined the feasibility of substituting Vero cells, cultured in the presence or absence of foetal bovine serum, for foetal rhesus lung-2 (FRhL-2) cells as the tissue culture substrate for the production of bPIV-3 vaccine. The results demonstrated that (i) Vero cell-produced bPIV-3 was as attenuated, immunogenic and efficacious as bPIV-3 vaccine grown in FRhL-2 cells, (ii) plasmid-derived bPIV-3 was as attenuated, immunogenic and efficacious as the biologically derived bPIV-3 and (iii) the b/hPIV-3 chimera displayed an intermediate attenuation phenotype and protected animals completely from hPIV-3 challenge. These results support the use of bPIV-3 vaccines propagated in Vero cells in human clinical trials and the use of b/hPIV-3 as a virus vaccine vector to express foreign viral antigens.

  1. Oncolytic vaccinia virotherapy of anaplastic thyroid cancer in vivo.

    Science.gov (United States)

    Lin, Shu-Fu; Price, Daniel L; Chen, Chun-Hao; Brader, Peter; Li, Sen; Gonzalez, Lorena; Zhang, Qian; Yu, Yong A; Chen, Nanhai; Szalay, Aladar A; Fong, Yuman; Wong, Richard J

    2008-11-01

    Anaplastic thyroid carcinoma (ATC) is a fatal disease with a median survival of only 6 months. Novel therapies are needed to improve dismal outcomes. A mutated, replication-competent, vaccinia virus (GLV-1h68) has oncolytic effects on human ATC cell lines in vitro. We assessed the utility of GLV-1h68 in treating anaplastic thyroid cancer in vivo. Athymic nude mice with xenograft flank tumors of human ATCs (8505C and DRO90-1) were treated with a single intratumoral injection of GLV-1h68 at low dose (5x10(5) plaque-forming unit), high dose (5x10(6) plaque-forming unit), or PBS. Virus-mediated marker gene expression (luciferase, green fluorescent protein, and beta-galactosidase), viral biodistribution, and flank tumor volumes were measured. Luciferase expression was detected 2 d after injection. Continuous viral replication within tumors was reflected by increasing luciferase activity to d 9. At d 10, tumor viral recovery was increased more than 50-fold as compared with the injected dose, and minimal virus was recovered from the lung, liver, brain, heart, spleen, and kidneys. High-dose virus directly injected into normal tissues was undetectable at d 10. The mean volume of control 8505C tumors increased 50.8-fold by d 45, in contrast to 10.5-fold (low dose) and 2.1-fold (high dose; P=0.028) increases for treated tumors. DRO90-1 tumors also showed significant growth inhibition by high-dose virus. No virus-related toxicity was observed throughout the study. GLV-1h68 efficiently infects, expresses transgenes within, and inhibits the growth of ATC in vivo. These promising findings support future clinical trials for patients with ATC.

  2. Towards targeted cancer therapy: Aptamer or oncolytic virus?

    Science.gov (United States)

    Tan, Kei X; Danquah, Michael K; Sidhu, Amandeep; Ongkudon, Clarence M; Lau, Sie Yon

    2017-01-01

    Cancer is a leading cause of global mortality. Whilst anticancer awareness programs have increased significantly over the years, scientific research into the development of efficient and specific drugs to target cancerous cells for enhanced therapeutic effects has not received much clinical success. Chemotherapeutic agents are incapable of acting specifically on cancerous cells, thus causing low therapeutic effects accompanied by toxicity to surrounding normal tissues. The search for smart, highly specific and efficient cancer treatments and delivery systems continues to be a significant research endeavor. Targeted cancer therapy is an evolving treatment approach with great promise in enhancing the efficacy of cancer therapies via the delivery of therapeutic agents specifically to and into desired tumor cells using viral or non-viral targeting elements. Viral oncotherapy is an advanced cancer therapy based on the use of oncolytic viruses (OV) as elements to specifically target, replicate and kill malignant cancer cells selectively without affecting surrounding healthy cells. Aptamers, on the other hand, are non-viral targeting elements that are single-stranded nucleic acids with high specificity, selectivity and binding affinity towards their cognate targets. Aptamers have emerged as a new class of bioaffinity targeting elements can be generated and molecularly engineered to selectively bind to diverse targets including proteins, cells and tissues. This article discusses, comparatively, the potentials and impacts of both viral and aptamer-mediated targeted cancer therapies in advancing conventional drug delivery systems through enhanced target specificity, therapeutic payload, bioavailability of the therapeutic agents at the target sites whilst minimizing systemic cytotoxicity. This article emphasizes on effective site-directed targeting mechanisms and efficacy issues that impact on clinical applications. Copyright © 2016 Elsevier B.V. All rights reserved.

  3. Oncolytic viruses as immunotherapy: progress and remaining challenges

    Directory of Open Access Journals (Sweden)

    Aurelian L

    2016-05-01

    Full Text Available Laure Aurelian Department of Pharmacology, University of Maryland School of Medicine, Baltimore, MD, USA Abstract: Oncolytic viruses (OVs comprise an emerging cancer therapeutic modality whose activity involves both direct tumor cell lysis and the induction of immunogenic cell death (ICD. Cellular proteins released from the OV-lysed tumor cells, known as damage-associated molecular patterns and tumor-associated antigens, activate dendritic cells and elicit adaptive antitumor immunity. Interaction with the innate immune system and the development of long-lasting immune memory also contribute to OV-induced cell death. The degree to which the ICD component contributes to the clinical efficacy of OV therapy is still unclear. Modulation of a range of immune interactions may be beneficial or detrimental in nature and the interactions depend on the specific tumor, the site and extent of the disease, the immunosuppressive tumor microenvironment, the OV platform, the dose, time, and delivery conditions, as well as individual patient responses. To enhance the contribution of ICD, OVs have been engineered to express immunostimulatory genes and strategies have been developed to combine OV therapy with chemo- and immune-based therapeutic regimens. However, these approaches carry the risk that they may also be tolerogenic depending on their levels and the presence of other cytokines, their direct antiviral effects, and the timing and conditions of their expression. The contribution of autophagy to adaptive immunity, the ability of the OVs to kill cancer stem cells, and the patient’s baseline immune status are additional considerations. This review focuses on the complex and as yet poorly understood balancing act that dictates the outcome of OV therapy. We summarize current understanding of the OVs’ function in eliciting antitumor immunity and its relationship to therapeutic efficacy. Also discussed are the criteria involved in restraining antiviral

  4. Herpes simplex virus type-1(HSV-1 oncolytic and highly fusogenic mutants carrying the NV1020 genomic deletion effectively inhibit primary and metastatic tumors in mice

    Directory of Open Access Journals (Sweden)

    David Andrew T

    2008-06-01

    Full Text Available Abstract Background The NV1020 oncolytic herpes simplex virus type-1 has shown significant promise for the treatment of many different types of tumors in experimental animal models and human trials. Previously, we described the construction and use of the NV1020-like virus OncSyn to treat human breast tumors implanted in nude mice. The syncytial mutation gKsyn1 (Ala-to-Val at position 40 was introduced into the OncSyn viral genome cloned into a bacterial artificial chromosome using double-red mutagenesis in E. coli to produce the OncdSyn virus carrying syncytial mutations in both gB(syn3 and gK(syn1. Results The OncdSyn virus caused extensive virus-induced cell fusion in cell culture. The oncolytic potential of the OncSyn and OncdSyn viruses was tested in the highly metastatic syngeneic mouse model system, which utilizes 4T1 murine mammary cancer cells implanted within the interscapular region of Balb/c mice. Mice were given three consecutive intratumor injections of OncSyn, OncdSyn, or phosphate buffered saline four days apart. Both OncSyn and OncdSyn virus injections resulted in significant reduction of tumor sizes (p Conclusion These results show that the attenuated, but highly fusogenic OncSyn and OncdSyn viruses can effectively reduce primary and metastatic breast tumors in immuncompetent mice. The available bac-cloned OncSyn and OncdSyn viral genomes can be rapidly modified to express a number of different anti-tumor and immunomodulatory genes that can further enhance their anti-tumor potency.

  5. Treatment of medulloblastoma with oncolytic measles viruses expressing the angiogenesis inhibitors endostatin and angiostatin.

    Science.gov (United States)

    Hutzen, Brian; Bid, Hemant Kumar; Houghton, Peter J; Pierson, Christopher R; Powell, Kimerly; Bratasz, Anna; Raffel, Corey; Studebaker, Adam W

    2014-03-19

    Medulloblastoma is the most common type of pediatric brain tumor. Although numerous factors influence patient survival rates, more than 30% of all cases will ultimately be refractory to conventional therapies. Current standards of care are also associated with significant morbidities, giving impetus for the development of new treatments. We have previously shown that oncolytic measles virotherapy is effective against medulloblastoma, leading to significant prolongation of survival and even cures in mouse xenograft models of localized and metastatic disease. Because medulloblastomas are known to be highly vascularized tumors, we reasoned that the addition of angiogenesis inhibitors could further enhance the efficacy of oncolytic measles virotherapy. Toward this end, we have engineered an oncolytic measles virus that express a fusion protein of endostatin and angiostatin, two endogenous and potent inhibitors of angiogenesis. Oncolytic measles viruses encoding human and mouse variants of a secretable endostatin/angiostatin fusion protein were designed and rescued according to established protocols. These viruses, known as MV-hE:A and MV-mE:A respectively, were then evaluated for their anti-angiogenic potential and efficacy against medulloblastoma cell lines and orthotopic mouse models of localized disease. Medulloblastoma cells infected by MV-E:A readily secrete endostatin and angiostatin prior to lysis. The inclusion of the endostatin/angiostatin gene did not negatively impact the measles virus' cytotoxicity against medulloblastoma cells or alter its growth kinetics. Conditioned media obtained from these infected cells was capable of inhibiting multiple angiogenic factors in vitro, significantly reducing endothelial cell tube formation, viability and migration compared to conditioned media derived from cells infected by a control measles virus. Mice that were given a single intratumoral injection of MV-E:A likewise showed reduced numbers of tumor-associated blood

  6. Combining Oncolytic Adenovirus with Radiation—A Paradigm for the Future of Radiosensitization

    Directory of Open Access Journals (Sweden)

    Sean M. O’Cathail

    2017-07-01

    Full Text Available Oncolytic viruses and radiotherapy represent two diverse areas of cancer therapy, utilizing quite different treatment modalities and with non-overlapping cytotoxicity profiles. It is, therefore, an intriguing possibility to consider that oncolytic (“cancer-killing” viruses may act as cancer-selective radiosensitizers, enhancing the therapeutic consequences of radiation treatment on tumors while exerting minimal effects on normal tissue. There is a solid mechanistic basis for this potential synergy, with many viruses having developed strategies to inhibit cellular DNA repair pathways in order to protect themselves, during genome replication, from unwanted interference by cell processes that are normally triggered by DNA damage. Exploiting these abilities to inhibit cellular DNA repair following damage by therapeutic irradiation may well augment the anticancer potency of the approach. In this review, we focus on oncolytic adenovirus, the most widely developed and best understood oncolytic virus, and explore its various mechanisms for modulating cellular DNA repair pathways. The most obvious effects of the various adenovirus serotypes are to interfere with activity of the MRE11-Rad50-Nbs1 complex, temporally one of the first sensors of double-stranded DNA damage, and inhibition of DNA ligase IV, a central repair enzyme for healing double-stranded breaks by non-homologous end joining (NHEJ. There have been several preclinical and clinical studies of this approach and we assess the current state of progress. In addition, oncolytic viruses provide the option to promote a localized proinflammatory response, both by mediating immunogenic death of cancer cells by oncosis and also by encoding and expressing proinflammatory biologics within the tumor microenvironment. Both of these approaches provide exciting potential to augment the known immunological consequences of radiotherapy, aiming to develop systems capable of creating a systemic anticancer

  7. Oncolytic Newcastle Disease Virus as Cutting Edge between Tumor and Host

    Directory of Open Access Journals (Sweden)

    Philippe Fournier

    2013-07-01

    Full Text Available Oncolytic viruses (OVs replicate selectively in tumor cells and exert anti-tumor cytotoxic activity. Among them, Newcastle Disease Virus (NDV, a bird RNA virus of the paramyxovirus family, appears outstanding. Its anti-tumor effect is based on: (i oncolytic activity and (ii immunostimulation. Together these activities facilitate the induction of post-oncolytic adaptive immunity. We will present milestones during the last 60 years of clinical evaluation of this virus. Two main strategies of clinical application were followed using the virus (i as a virotherapeutic agent, which is applied systemically or (ii as an immunostimulatory agent combined with tumor cells for vaccination of cancer patients. More recently, a third strategy evolved. It combines the strategies (i and (ii and includes also dendritic cells (DCs. The first step involves systemic application of NDV to condition the patient. The second step involves intradermal application of a special DC vaccine pulsed with viral oncolysate. This strategy, called NDV/DC, combines anti-cancer activity (oncolytic virotherapy and immune-stimulatory properties (oncolytic immunotherapy with the high potential of DCs (DC therapy to prime naive T cells. The aim of such treatment is to first prepare the cancer-bearing host for immunocompetence and then to instruct the patient’s immune system with information about tumor-associated antigens (TAAs of its own tumor together with danger signals derived from virus infection. This multimodal concept should optimize the generation of strong polyclonal T cell reactivity targeted against the patient’s TAAs and lead to the establishment of a long-lasting memory T cell repertoire.

  8. Conditionally replicative adenovirus expressing a targeting adapter molecule exhibits enhanced oncolytic potency on CAR-deficient tumors

    NARCIS (Netherlands)

    van Beusechem, V.W.; Mastenbroek, D.C.; Van den Doel, P.B.; Lamfers, M.L.; Grill, J.; Wurdinger, T.; Haisma, H.J.; Pinedo, H.M.; Gerritsen, W.R.

    2003-01-01

    Conditionally replicative adenoviruses (CRAds) are potentially useful agents for anticancer virotherapy approaches. However, lack of coxsackievirus and adenovirus receptor ( CAR) expression on many primary tumor cells limits the oncolytic potency of CRAds. This makes the concept of targeting, that

  9. The live-attenuated yellow fever vaccine 17D induces broad and potent T cell responses against several viral proteins in Indian rhesus macaques – implications for recombinant vaccine design

    OpenAIRE

    Mudd, Philip A.; Piaskowski, Shari M.; Neves, Patricia C. Costa; Rudersdorf, Richard; Kolar, Holly L.; Eernisse, Christopher M.; Weisgrau, Kim L.; Veloso de Santana, Marlon G.; Wilson, Nancy A.; Bonaldo, Myrna C.; Galler, Ricardo; Rakasz, Eva G.; Watkins, David I.

    2010-01-01

    The yellow fever vaccine 17D (YF17D) is one of the most effective vaccines. Its wide use and favorable safety profile make it a prime candidate for recombinant vaccines. It is believed that neutralizing antibodies account for a large measure of the protection afforded to YF17D-vaccinated individuals, however cytotoxic T lymphocyte (CTL) responses have been described in the setting of YF17D vaccination. YF17D is an ssRNA flavivirus that is translated as a full-length polyprotein, several domai...

  10. GP73-regulated oncolytic adenoviruses possess potent killing effect on human liver cancer stem-like cells

    OpenAIRE

    Zhang, Xinmin; Meng, Shulin; Zhang, Rong; Ma, Buyun; Yang, Yu; Xie, Wenjie; Liu, Xianglei; Huang, Fang; Liu, Tao; Zhou, Xiumei; Liu, Xinyuan; Wang, Yigang

    2016-01-01

    Cancer stem cells (CSCs), also known as tumor-initiating cells, are highly metastatic, chemo-resistant and tumorigenic, and are critical for cancer development, maintenance and recurrence. Oncolytic adenovirus could targetedly kill CSCs and has been acted as a promising anticancer agent. Currently, a novel GP73-regulated oncolytic adenovirus GD55 was constructed to specifically treat liver cancer and exhibited obvious cytotoxicity effect. However, there remains to be confirmed that whether GD...

  11. Targeting Localized Immune Suppression Within the Tumor Through Repeat Cycles of Immune Cell-oncolytic Virus Combination Therapy

    OpenAIRE

    Thorne, Stephen H; Liang, Wenchun; Sampath, Padma; Schmidt, Tobi; Sikorski, Rachel; Beilhack, Andreas; Contag, Christopher H.

    2010-01-01

    A major limitation to the use of immunotherapy in the treatment of cancer has been the localized immune suppressive environment within the tumor. Although there is evidence that tumor-selective (oncolytic) viruses may help to overcome this immune suppression, a primary limitation to their use has been limited systemic delivery potential, especially in the face of antiviral immunity. We recently demonstrated that tumor-trafficking immune cells can efficiently deliver oncolytic viral therapies ...

  12. The viral tropism of two distinct oncolytic viruses, reovirus and myxoma virus, is modulated by cellular tumor suppressor gene status

    OpenAIRE

    Kim, M.; Williamson, CT; Prudhomme, J.; Bebb, DG; Riabowol, K; Lee, PWK; Lees-Miller, SP; Mori, Y; Rahman, MM; McFadden, G; Johnston, RN

    2010-01-01

    Replication-competent oncolytic viruses hold great potential for the clinical treatment of many cancers. Importantly, many oncolytic virus candidates, such as reovirus and myxoma virus, preferentially infect cancer cells bearing abnormal cellular signaling pathways. Reovirus and myxoma virus are highly responsive to activated Ras and Akt signaling pathways, respectively, for their specificity for viral oncolysis. However, considering the complexity of cancer cell populations, it is possible t...

  13. Expression of DAI by an oncolytic vaccinia virus boosts the immunogenicity of the virus and enhances antitumor immunity

    Directory of Open Access Journals (Sweden)

    Mari Hirvinen

    2016-01-01

    Full Text Available In oncolytic virotherapy, the ability of the virus to activate the immune system is a key attribute with regard to long-term antitumor effects. Vaccinia viruses bear one of the strongest oncolytic activities among all oncolytic viruses. However, its capacity for stimulation of antitumor immunity is not optimal, mainly due to its immunosuppressive nature. To overcome this problem, we developed an oncolytic VV that expresses intracellular pattern recognition receptor DNA-dependent activator of IFN-regulatory factors (DAI to boost the innate immune system and to activate adaptive immune cells in the tumor. We showed that infection with DAI-expressing VV increases expression of several genes related to important immunological pathways. Treatment with DAI-armed VV resulted in significant reduction in the size of syngeneic melanoma tumors in mice. When the mice were rechallenged with the same tumor, DAI-VV-treated mice completely rejected growth of the new tumor, which indicates immunity established against the tumor. We also showed enhanced control of growth of human melanoma tumors and elevated levels of human T-cells in DAI-VV-treated mice humanized with human peripheral blood mononuclear cells. We conclude that expression of DAI by an oncolytic VV is a promising way to amplify the vaccine potency of an oncolytic vaccinia virus to trigger the innate—and eventually the long-lasting adaptive immunity against cancer.

  14. Fc-gamma receptor polymorphisms as predictive and prognostic factors in patients receiving oncolytic adenovirus treatment

    Science.gov (United States)

    2013-01-01

    Background Oncolytic viruses have shown potential as cancer therapeutics, but not all patients seem to benefit from therapy. Polymorphisms in Fc gamma receptors (FcgRs) lead to altered binding affinity of IgG between the receptor allotypes and therefore contribute to differences in immune defense mechanisms. Associations have been identified between FcgR polymorphisms and responsiveness to different immunotherapies. Taken together with the increasing understanding that immunological factors might determine the efficacy of oncolytic virotherapy we studied whether FcgR polymorphisms would have prognostic and/or predictive significance in the context of oncolytic adenovirus treatments. Methods 235 patients with advanced solid tumors were genotyped for two FcgR polymorphisms, FcgRIIa-H131R (rs1801274) and FcgRIIIa-V158F (rs396991), using TaqMan based qPCR. The genotypes were correlated with patient survival and tumor imaging data. Results In patients treated with oncolytic adenoviruses, overall survival was significantly shorter if the patient had an FcgRIIIa-VV/ FcgRIIa-HR (VVHR) genotype combination (P = 0,032). In contrast, patients with FFHR and FFRR genotypes had significantly longer overall survival (P = 0,004 and P = 0,006, respectively) if they were treated with GM-CSF-armed adenovirus in comparison to other viruses. Treatment of these patients with unarmed virus correlated with shorter survival (P treatment with other viruses (P = 0,047). Conclusions Our data are compatible with the hypothesis that individual differences in effector cell functions, such as NK cell-mediated antibody-dependent cellular cytotoxicity (ADCC) and tumor antigen presentation by APCs caused by polymorphisms in FcgRs could play role in the effectiveness of oncolytic virotherapies. If confirmed in larger populations, FcgR polymorphisms could have potential as prognostic and predictive biomarkers for oncolytic adenovirus therapies to enable better selection of patients

  15. Therapeutic Use of Native and Recombinant Enteroviruses.

    Science.gov (United States)

    Ylä-Pelto, Jani; Tripathi, Lav; Susi, Petri

    2016-02-23

    Research on human enteroviruses has resulted in the identification of more than 100 enterovirus types, which use more than 10 protein receptors and/or attachment factors required in cell binding and initiation of the replication cycle. Many of these "viral" receptors are overexpressed in cancer cells. Receptor binding and the ability to replicate in specific target cells define the tropism and pathogenesis of enterovirus types, because cellular infection often results in cytolytic response, i.e., disruption of the cells. Viral tropism and cytolytic properties thus make native enteroviruses prime candidates for oncolytic virotherapy. Copy DNA cloning and modification of enterovirus genomes have resulted in the generation of enterovirus vectors with properties that are useful in therapy or in vaccine trials where foreign antigenic epitopes are expressed from or on the surface of the vector virus. The small genome size and compact particle structure, however, set limits to enterovirus genome modifications. This review focuses on the therapeutic use of native and recombinant enteroviruses and the methods that have been applied to modify enterovirus genomes for therapy.

  16. Therapeutic Use of Native and Recombinant Enteroviruses

    Directory of Open Access Journals (Sweden)

    Jani Ylä-Pelto

    2016-02-01

    Full Text Available Research on human enteroviruses has resulted in the identification of more than 100 enterovirus types, which use more than 10 protein receptors and/or attachment factors required in cell binding and initiation of the replication cycle. Many of these “viral” receptors are overexpressed in cancer cells. Receptor binding and the ability to replicate in specific target cells define the tropism and pathogenesis of enterovirus types, because cellular infection often results in cytolytic response, i.e., disruption of the cells. Viral tropism and cytolytic properties thus make native enteroviruses prime candidates for oncolytic virotherapy. Copy DNA cloning and modification of enterovirus genomes have resulted in the generation of enterovirus vectors with properties that are useful in therapy or in vaccine trials where foreign antigenic epitopes are expressed from or on the surface of the vector virus. The small genome size and compact particle structure, however, set limits to enterovirus genome modifications. This review focuses on the therapeutic use of native and recombinant enteroviruses and the methods that have been applied to modify enterovirus genomes for therapy.

  17. 4th European Seminars in Virology on Oncogenic and Oncolytic Viruses, in Bertinoro (Bologna), Italy.

    Science.gov (United States)

    Reale, Alberto; Messa, Lorenzo; Vitiello, Adriana; Loregian, Arianna; Palù, Giorgio

    2017-10-01

    The 4th European Seminars in Virology (EuSeV), which was focused on oncogenic and oncolytic viruses, was held in Bertinoro (Bologna), Italy, from June 10 to 12, 2016. This article summarizes the plenary lectures and aims to illustrate the main topics discussed at 4th EuSeV, which brought together knowledge and expertise in the field of oncogenic and oncolytic viruses from all over the world. The meeting was divided in two parts, "Mechanisms of Viral Oncogenesis" and "Viral Oncolysis and Immunotherapy," which were both focused on dissecting the complex and multi-factorial interplay between cancer and human viruses and on exploring new anti-cancer strategies. J. Cell. Physiol. 232: 2641-2648, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  18. ET-17TRANSIENT FASTING ENHANCES REPLICATION AND THERAPEUTIC ACTIVITY OF ONCOLYTIC HSV IN GLIOBLASTOMA THERAPY

    OpenAIRE

    Esaki, Shinichi; Rabkin, Samuel D; Martuza, Robert L; Wakimoto, Hiroaki

    2014-01-01

    BACKGROUND AND OBJECTIVE: Short term fasting has been shown to enhance efficacy of chemotherapy by sensitizing tumor cells and protecting normal cells in a variety of cancer models including glioblastoma (GBM). Malignant cells, unlike normal cells, respond to fasting by promoting oncogenic signaling and protein synthesis, which could in turn sensitize them to anti-cancer agents, broadening therapeutic window. We hypothesize that fasting increases replication of oncolytic herpes simplex virus ...

  19. Oncolytic virotherapy for malignant glioma: translating laboratory insights into clinical practice

    OpenAIRE

    Auffinger, Brenda; Ahmed, Atique U.; Lesniak, Maciej S.

    2013-01-01

    Glioblastoma multiforme, one of the most common and aggressive brain tumors in adults, is highly resistant to currently available therapies and often recurs. Due to its poor prognosis and difficult management, there is an urgent need for the development and translation of new anti-glioma therapeutic approaches into the clinic. In this context, oncolytic virotherapy arises as an exciting treatment option for glioma patients. These natural or genetically engineered viruses are able to effective...

  20. Intraventricular Delivery of Engineered Oncolytic Herpes Simplex Virotherapy to Treat Localized and Metastatic Pediatric Brain Tumors

    Science.gov (United States)

    2016-08-01

    by neurotoxicity for the developing brain caused by current therapies. Oncolytic HSV (oHSV) offers an inventive , targeted, less-toxic approach for...has closed: Hyundai Hope on Wheels Friedman, Gregory K (PI) 10/01/13-09/30/15 1.0 cal-mos Pending grant...overlap. Page 18 Pending grant: Hyundai Hope on Wheels Friedman Gregory K (PI) 12/31/16-12/30/18 0.6 cal-mos Enhancement of Immunovirotherapy

  1. Overcoming Barriers in Oncolytic Virotherapy with HDAC Inhibitors and Immune Checkpoint Blockade

    Science.gov (United States)

    Marchini, Antonio; Scott, Eleanor M.; Rommelaere, Jean

    2016-01-01

    Oncolytic viruses (OVs) target and destroy cancer cells while sparing their normal counterparts. These viruses have been evaluated in numerous studies at both pre-clinical and clinical levels and the recent Food and Drug Administration (FDA) approval of an oncolytic herpesvirus-based treatment raises optimism that OVs will become a therapeutic option for cancer patients. However, to improve clinical outcome, there is a need to increase OV efficacy. In addition to killing cancer cells directly through lysis, OVs can stimulate the induction of anti-tumour immune responses. The host immune system thus represents a “double-edged sword” for oncolytic virotherapy: on the one hand, a robust anti-viral response will limit OV replication and spread; on the other hand, the immune-mediated component of OV therapy may be its most important anti-cancer mechanism. Although the relative contribution of direct viral oncolysis and indirect, immune-mediated oncosuppression to overall OV efficacy is unclear, it is likely that an initial period of vigorous OV multiplication and lytic activity will most optimally set the stage for subsequent adaptive anti-tumour immunity. In this review, we consider the use of histone deacetylase (HDAC) inhibitors as a means of boosting virus replication and lessening the negative impact of innate immunity on the direct oncolytic effect. We also discuss an alternative approach, aimed at potentiating OV-elicited anti-tumour immunity through the blockade of immune checkpoints. We conclude by proposing a two-phase combinatorial strategy in which initial OV replication and spread is maximised through transient HDAC inhibition, with anti-tumour immune responses subsequently enhanced by immune checkpoint blockade. PMID:26751469

  2. The immunoregulatory properties of oncolytic myxoma virus and their implications in therapeutics.

    Science.gov (United States)

    Liu, Jia; Wennier, Sonia; McFadden, Grant

    2010-12-01

    Myxoma virus (MYXV) is a poxvirus with a strict rabbit-specific host-tropism for pathogenesis. The immunoregulatory factors encoded by MYXV can suppress some functions of immune effectors from other species. We review their mechanisms of action, implications in therapeutics and the potential to improve MYXV as an oncolytic agent in humans. Copyright © 2010 Institut Pasteur. Published by Elsevier SAS. All rights reserved.

  3. Myxoma Virus Is a Novel Oncolytic Virus with Significant Antitumor Activity against Experimental Human Gliomas

    OpenAIRE

    Lun, Xueqing; Yang, Wenqing; Alain, Tommy; Shi, Zhong-Qiao; Muzik, Huong; Barrett, John W.; McFadden, Grant; Bell, John; Hamilton, Mark G.; Senger, Donna L.; Forsyth, Peter A.

    2005-01-01

    Myxoma virus, a poxvirus previously considered rabbit specific, can replicate productively in a variety of human tumor cells in culture. The purpose of this study was to determine if there was efficacy or toxicities of this oncolytic virus against experimental models of human malignant gliomas in vitro, in vivo, and ex vivo in malignant glioma specimens. In vitro, the majority of glioma cell lines tested (7 of 8, 87.5%) were fully permissive for myxoma virus replication and killed by infectio...

  4. Systemic therapy with oncolytic myxoma virus cures established residual multiple myeloma in mice

    OpenAIRE

    Bartee, Eric; Bartee, Mee Y.; Bogen, Bjarne; Yu, Xue-Zhong

    2016-01-01

    Multiple myeloma is an incurable malignancy of plasma B-cells. Traditional chemotherapeutic regimes often induce initial tumor regression; however, virtually all patients eventually succumb to relapse caused by either reintroduction of disease during autologous transplant or expansion of chemotherapy resistant minimal residual disease. It has been previously demonstrated that an oncolytic virus known as myxoma can completely prevent myeloma relapse caused by reintroduction of malignant cells ...

  5. Evidence for differential viral oncolytic efficacy in an in vitro model of epithelial ovarian cancer metastasis

    OpenAIRE

    Jessica G Tong; Valdes, Yudith Ramos; Barrett, John W.; Bell, John C; Stojdl, David; McFadden, Grant; McCart, J Andrea; DiMattia, Gabriel E; Trevor G Shepherd

    2015-01-01

    Epithelial ovarian cancer is unique among most carcinomas in that metastasis occurs by direct dissemination of malignant cells traversing throughout the intraperitoneal fluid. Accordingly, we test new therapeutic strategies using an in vitro three-dimensional spheroid suspension culture model that mimics key steps of this metastatic process. In the present study, we sought to uncover the differential oncolytic efficacy among three different viruses—Myxoma virus, double-deleted vaccinia virus,...

  6. Combinatorial treatment with oncolytic adenovirus and helper-dependent adenovirus augments adenoviral cancer gene therapy.

    Science.gov (United States)

    Farzad, Lisa; Cerullo, Vincenzo; Yagyu, Shigeki; Bertin, Terry; Hemminki, Akseli; Rooney, Cliona; Lee, Brendan; Suzuki, Masataka

    2014-01-01

    Oncolytic adenoviruses (Onc.Ads) produce significant antitumor effects but as single agents they rarely eliminate tumors. Investigators have therefore incorporated sequences into these vectors that encode immunomodulatory molecules to enhance antitumor immunity. Successful implementation of this strategy requires multiple tumor immune inhibitory mechanisms to be overcome, and insertion of the corresponding multiple functional genes reduces the titer and replication of Onc.Ads, compromising their direct ant-tumor effects. By contrast, helper-dependent (HD) Ads are devoid of viral coding sequences, allowing inclusion of multiple transgenes. HDAds, however, lack replicative capacity. Since HDAds encode the adenoviral packaging signal, we hypothesized that the coadministration of Onc.Ad with HDAd would allow to be amplified and packaged during replication of Onc.Ad in transduced cancer cells. This combination could provide immunostimulation without losing oncolytic activity. We now show that coinfection of Onc.Ad with HDAd subsequently replicates HDAd vector DNA in trans in human cancer cell lines in vitro and in vivo, amplifying the transgenes the HDAd encode. This combinatorial treatment significantly suppresses the tumor growth compared to treatment with a single agent in an immunocompetent mouse model. Hence, combinatorial treatment of Onc.Ad with HDAd should overcome the inherent limitations of each agent and provide a highly immunogenic oncolytic therapy.

  7. VSV oncolytic virotherapy in the B16 model depends upon intact MyD88 signaling.

    Science.gov (United States)

    Wongthida, Phonphimon; Diaz, Rosa M; Galivo, Feorillo; Kottke, Timothy; Thompson, Jill; Melcher, Alan; Vile, Richard

    2011-01-01

    We show here, for the first time to our knowledge, that the antitumor therapy of oncolytic vesicular stomatitis virus (VSV) in the B16ova model depends upon signaling through myeloid differentiation primary response gene 88 (MyD88) in host cells. VSV-mediated therapy of B16ova tumors was abolished in MyD88(-/-) mice despite generation of antigen-specific T cell responses similar to those in immune-competent mice. Mice defective in only toll-like receptor 4 (TLR4), TLR7, or interleukin 1 (IL-1) signaling retained VSV-induced therapy, suggesting that multiple, redundant pathways of innate immune activation by the virus contribute to antitumor immune reactivity. Lack of MyD88 signaling was associated with decreased expression of proinflammatory cytokines and neutrophil infiltration in response to intratumoral virus, as well as decreased infiltration of draining lymph nodes (LN) with plasmacytoid dendritic cells (pDCs) (CD11b(-)GR1(+)B220(+)) and myeloid-derived suppressor cells (CD11b(+)GR1(+)F4/80(+)). MyD88 signaling in response to VSV was also closely associated with a type I interferon (IFN) response. This inhibited virus replication within the tumor but also protected the host from viral dissemination from the tumor. Therefore, the innate immune response to oncolytic viruses can be, simultaneously, protherapeutic, antioncolytic, and systemically protective. These paradoxically conflicting roles need to be carefully considered in future strategies designed to improve the efficacy of oncolytic virotherapy.

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

    Directory of Open Access Journals (Sweden)

    Kaname Nosaki

    2016-01-01

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

  9. N-Myc expression enhances the oncolytic effects of vesicular stomatitis virus in human neuroblastoma cells

    Directory of Open Access Journals (Sweden)

    Juan C Corredor

    2016-01-01

    Full Text Available N-myc oncogene amplification is associated but not present in all cases of high-risk neuroblastoma (NB. Since oncogene expression could often modulate sensitivity to oncolytic viruses, we wanted to examine if N-myc expression status would determine virotherapy efficacy to high-risk NB. We showed that induction of exogenous N-myc in a non-N-myc-amplified cell line background (TET-21N increased susceptibility to oncolytic vesicular stomatitis virus (mutant VSVδM51 and alleviated the type I IFN-induced antiviral state. Cells with basal N-myc, on the other hand, were less susceptible to virus-induced oncolysis and established a robust IFN-mediated antiviral state. The same effects were also observed in NB cell lines with and without N-myc amplification. Microarray analysis showed that N-myc overexpression in TET-21N cells downregulated IFN-stimulated genes (ISGs with known antiviral functions. Furthermore, virus infection caused significant changes in global gene expression in TET-21N cells overexpressing N-myc. Such changes involved ISGs with various functions. Therefore, the present study showed that augmented susceptibility to VSVδM51 by N-myc at least involves downregulation of ISGs with antiviral functions and alleviation of the IFN-stimulated antiviral state. Our studies suggest the potential utility of N-myc amplification/overexpression as a predictive biomarker of virotherapy response for high-risk NB using IFN-sensitive oncolytic viruses.

  10. Oncolytic Herpes Simplex Virus Inhibits Pediatric Brain Tumor Migration and Invasion

    Directory of Open Access Journals (Sweden)

    Julia V. Cockle

    2017-06-01

    Full Text Available Pediatric high-grade glioma (pHGG and diffuse intrinsic pontine glioma (DIPG are invasive tumors with poor survival. Oncolytic virotherapy, initially devised as a direct cytotoxic treatment, is now also known to act via immune-mediated mechanisms. Here we investigate a previously unreported mechanism of action: the inhibition of migration and invasion in pediatric brain tumors. We evaluated the effect of oncolytic herpes simplex virus 1716 (HSV1716 on the migration and invasion of pHGG and DIPG both in vitro using 2D (scratch assay, live cell imaging and 3D (spheroid invasion in collagen assays and in vivo using an orthotopic xenograft model of DIPG invasion. HSV1716 inhibited migration and invasion in pHGG and DIPG cell lines. pHGG cells demonstrated reduced velocity and changed morphology in the presence of virus. HSV1716 altered pHGG cytoskeletal dynamics by stabilizing microtubules, inhibiting glycogen synthase kinase-3, and preventing localized clustering of adenomatous polyposis coli (APC to the leading edge of cells. HSV1716 treatment also reduced tumor infiltration in a mouse orthotopic xenograft DIPG model. Our results demonstrate that HSV1716 targets the migration and invasion of pHGG and DIPG and indicates the potential of an oncolytic virus (OV to be used as a novel anti-invasive treatment strategy for pediatric brain tumors.

  11. Oncolytic Viruses—Interaction of Virus and Tumor Cells in the Battle to Eliminate Cancer

    Science.gov (United States)

    Howells, Anwen; Marelli, Giulia; Lemoine, Nicholas R.; Wang, Yaohe

    2017-01-01

    Oncolytic viruses (OVs) are an emerging treatment option for many cancer types and have recently been the focus of extensive research aiming to develop their therapeutic potential. The ultimate aim is to design a virus which can effectively replicate within the host, specifically target and lyse tumor cells and induce robust, long lasting tumor-specific immunity. There are a number of viruses which are either naturally tumor-selective or can be modified to specifically target and eliminate tumor cells. This means they are able to infect only tumor cells and healthy tissue remains unharmed. This specificity is imperative in order to reduce the side effects of oncolytic virotherapy. These viruses can also be modified by various methods including insertion and deletion of specific genes with the aim of improving their efficacy and safety profiles. In this review, we have provided an overview of the various virus species currently being investigated for their oncolytic potential and the positive and negative effects of a multitude of modifications used to increase their infectivity, anti-tumor immunity, and treatment safety, in particular focusing on the interaction of tumor cells and OVs. PMID:28944214

  12. Oncolytic Viruses-Interaction of Virus and Tumor Cells in the Battle to Eliminate Cancer.

    Science.gov (United States)

    Howells, Anwen; Marelli, Giulia; Lemoine, Nicholas R; Wang, Yaohe

    2017-01-01

    Oncolytic viruses (OVs) are an emerging treatment option for many cancer types and have recently been the focus of extensive research aiming to develop their therapeutic potential. The ultimate aim is to design a virus which can effectively replicate within the host, specifically target and lyse tumor cells and induce robust, long lasting tumor-specific immunity. There are a number of viruses which are either naturally tumor-selective or can be modified to specifically target and eliminate tumor cells. This means they are able to infect only tumor cells and healthy tissue remains unharmed. This specificity is imperative in order to reduce the side effects of oncolytic virotherapy. These viruses can also be modified by various methods including insertion and deletion of specific genes with the aim of improving their efficacy and safety profiles. In this review, we have provided an overview of the various virus species currently being investigated for their oncolytic potential and the positive and negative effects of a multitude of modifications used to increase their infectivity, anti-tumor immunity, and treatment safety, in particular focusing on the interaction of tumor cells and OVs.

  13. T-cell Subsets in Peripheral Blood and Tumors of Patients Treated With Oncolytic Adenoviruses

    Science.gov (United States)

    Kristian, Taipale; Ilkka, Liikanen; Juuso, Juhila; Aila, Karioja-Kallio; Minna, Oksanen; Riku, Turkki; Nina, Linder; Johan, Lundin; Ari, Ristimäki; Anna, Kanerva; Anniina, Koski; Timo, Joensuu; Markus, Vähä-Koskela; Akseli, Hemminki

    2015-01-01

    The quality of the antitumor immune response is decisive when developing new immunotherapies for cancer. Oncolytic adenoviruses cause a potent immunogenic stimulus and arming them with costimulatory molecules reshapes the immune response further. We evaluated peripheral blood T-cell subsets of 50 patients with refractory solid tumors undergoing treatment with oncolytic adenovirus. These data were compared to changes in antiviral and antitumor T cells, treatment efficacy, overall survival, and T-cell subsets in pre- and post-treatment tumor biopsies. Treatment caused a significant (P < 0.0001) shift in T-cell subsets in blood, characterized by a proportional increase of CD8+ cells, and decrease of CD4+ cells. Concomitant treatment with cyclophosphamide and temozolomide resulted in less CD4+ decrease (P = 0.041) than cyclophosphamide only. Interestingly, we saw a correlation between T-cell changes in peripheral blood and the tumor site. This correlation was positive for CD8+ and inverse for CD4+ cells. These findings give insight to the interconnections between peripheral blood and tumor-infiltrating lymphocyte (TIL) populations regarding oncolytic virotherapy. In particular, our data suggest that induction of T-cell response is not sufficient for clinical response in the context of immunosuppressive tumors, and that peripheral blood T cells have a complicated and potentially misleading relationship with TILs. PMID:25655312

  14. Transient fasting enhances replication of oncolytic herpes simplex virus in glioblastoma

    Science.gov (United States)

    Esaki, Shinichi; Rabkin, Samuel D; Martuza, Robert L; Wakimoto, Hiroaki

    2016-01-01

    Short-term nutritional restriction (fasting) has been shown to enhance the efficacy of chemotherapy by sensitizing cancer cells and protecting normal cells in a variety of cancer models, including glioblastoma (GBM). Cancer cells, unlike normal cells, respond to fasting by promoting oncogenic signaling and protein synthesis. We hypothesized that fasting would increase the replication of oncolytic herpes simplex virus (oHSV) in GBM. Patient-derived GBM cell lines were fasted by growth in glucose and fetal calf serum restricted culture medium. “Transient fasting”, 24-hour fasting followed by 24-hour recovery in complete medium, increased late virus gene expression and G47Δ yields about 2-fold in GBM cells, but not in human astrocytes, and enhanced G47Δ killing of GBM cells. Mechanistically, “transient fasting” suppressed phosphorylation of the subunit of eukaryotic initiation factor 2α (eIF2α) and c-Jun N-terminal kinases (JNK) in GBM cells, but not in astrocytes. Pharmacological inhibition of JNK also increased G47Δ yield. In vivo, transient fasting (48-hour food restriction and 24-hour recovery) doubled luciferase activity after intratumoral G47Δ-US11fluc injection into orthotopic GBM xenografts. Thus, “transient fasting” increases G47Δ replication and oncolytic activity in human GBM cells. These results suggest that “transient fasting” may be effectively combined to enhance oncolytic HSV therapy of GBM. PMID:27186404

  15. Preclinical evaluation of oncolytic vaccinia virus for therapy of canine soft tissue sarcoma.

    Directory of Open Access Journals (Sweden)

    Ivaylo Gentschev

    Full Text Available Virotherapy using oncolytic vaccinia virus (VACV strains is one promising new strategy for canine cancer therapy. In this study we describe the establishment of an in vivo model of canine soft tissue sarcoma (CSTS using the new isolated cell line STSA-1 and the analysis of the virus-mediated oncolytic and immunological effects of two different Lister VACV LIVP1.1.1 and GLV-1h68 strains against CSTS. Cell culture data demonstrated that both tested VACV strains efficiently infected and destroyed cells of the canine soft tissue sarcoma line STSA-1. In addition, in our new canine sarcoma tumor xenograft mouse model, systemic administration of LIVP1.1.1 or GLV-1h68 viruses led to significant inhibition of tumor growth compared to control mice. Furthermore, LIVP1.1.1 mediated therapy resulted in almost complete tumor regression and resulted in long-term survival of sarcoma-bearing mice. The replication of the tested VACV strains in tumor tissues led to strong oncolytic effects accompanied by an intense intratumoral infiltration of host immune cells, mainly neutrophils. These findings suggest that the direct viral oncolysis of tumor cells and the virus-dependent activation of tumor-associated host immune cells could be crucial parts of anti-tumor mechanism in STSA-1 xenografts. In summary, the data showed that both tested vaccinia virus strains and especially LIVP1.1.1 have great potential for effective treatment of CSTS.

  16. Crosstalk between immune cell and oncolytic vaccinia therapy enhances tumor trafficking and antitumor effects.

    Science.gov (United States)

    Sampath, Padma; Li, Jun; Hou, Weizhou; Chen, Hannah; Bartlett, David L; Thorne, Steve H

    2013-03-01

    The combination of an oncolytic virus, that directly destroys tumor cells and mediates an acute immune response, with an immune cell therapy, capable of further enlisting and enhancing the host immune response, has the potential to create a potent therapeutic effect. We have previously developed several strategies for optimizing the delivery of oncolytic vaccinia virus vectors to their tumor targets, including the use of immune cell-based carrier vehicles and the incorporation of mutations that increase production of the enveloped form of vaccinia (extracellular enveloped viral (EEV)) that is better adapted to spread within a host. Here, we initially combine these approaches to create a novel therapeutic, consisting of an immune cell (cytokine-induced killer, CIK) preloaded with an oncolytic virus that is EEV enhanced. This resulted in direct interaction between the viral and immune cell components with each assisting the other in directing the therapy to the tumor and so enhancing the antitumor effects. This effect could be further improved through CCL5 expression from the virus. The resulting multicomponent therapy displays the ability for synergistic crosstalk between components, so significantly enhancing tumor trafficking and antitumor effects.

  17. Targeting human medulloblastoma: oncolytic virotherapy with myxoma virus is enhanced by rapamycin.

    Science.gov (United States)

    Lun, Xue Qing; Zhou, Hongyuan; Alain, Tommy; Sun, Beichen; Wang, Limei; Barrett, John W; Stanford, Marianne M; McFadden, Grant; Bell, John; Senger, Donna L; Forsyth, Peter A

    2007-09-15

    We have shown previously the oncolytic potential of myxoma virus in a murine xenograft model of human glioma. Here, we show that myxoma virus used alone or in combination with rapamycin is effective and safe when used in experimental models of medulloblastoma in vitro and in vivo. Nine of 10 medulloblastoma cell lines tested were susceptible to lethal myxoma virus infection, and pretreatment of cells with rapamycin increased the extent of in vitro oncolysis. Intratumoral injection of live myxoma virus when compared with control inactivated virus prolonged survival in D341 and Daoy orthotopic human medulloblastoma xenograft mouse models [D341 median survival: 21 versus 12.5 days; P = 0.0008; Daoy median survival: not reached (three of five mice apparently "cured" after 223 days) versus 75 days; P = 0.0021]. Rapamycin increased the extent of viral oncolysis, "curing" most Daoy tumor-bearing mice and reducing or eliminating spinal cord and ventricle metastases. Rapamycin enhanced tumor-specific myxoma virus replication in vivo and prolonged survival of D341 tumor-bearing mice (median survival of mice treated with live virus (LV) and rapamycin, versus LV alone, versus rapamycin alone, versus inactivated virus: 25 days versus 19, 13, and 11 days, respectively; P myxoma virus oncolysis. These observations suggest that myxoma virus may be an effective oncolytic agent against medulloblastoma and that combination therapy with signaling inhibitors that modulate activity of the phosphatidylinositol 3-kinase/Akt pathway will further enhance the oncolytic potential of myxoma virus.

  18. The ex vivo purge of cancer cells using oncolytic viruses: recent advances and clinical implications.

    Science.gov (United States)

    Tsang, Jovian J; Atkins, Harold L

    2015-01-01

    Hematological malignancies are treated with intensive high-dose chemotherapy, with or without radiation. This is followed by hematopoietic stem cell (HSC) transplantation (HSCT) to rescue or reconstitute hematopoiesis damaged by the anticancer therapy. Autologous HSC grafts may contain cancer cells and purging could further improve treatment outcomes. Similarly, allogeneic HSCT may be improved by selectively purging alloreactive effector cells from the graft rather than wholesale immune cell depletion. Viral agents that selectively replicate in specific cell populations are being studied in experimental models of cancer and immunological diseases and have potential applications in the context of HSC graft engineering. This review describes preclinical studies involving oncolytic virus strains of adenovirus, herpes simplex virus type 1, myxoma virus, and reovirus as ex vivo purging agents for HSC grafts, as well as in vitro and in vivo experimental studies using oncolytic coxsackievirus, measles virus, parvovirus, vaccinia virus, and vesicular stomatitis virus to eradicate hematopoietic malignancies. Alternative ex vivo oncolytic virus strategies are also outlined that aim to reduce the risk of relapse following autologous HSCT and mitigate morbidity and mortality due to graft-versus-host disease in allogeneic HSCT.

  19. Oncolytic virotherapy synergism with signaling inhibitors: Rapamycin increases myxoma virus tropism for human tumor cells.

    Science.gov (United States)

    Stanford, Marianne M; Barrett, John W; Nazarian, Steven H; Werden, Steven; McFadden, Grant

    2007-02-01

    Myxoma virus is a rabbit-specific poxvirus pathogen that also exhibits a unique tropism for human tumor cells and is dramatically oncolytic for human cancer xenografts. Most tumor cell lines tested are permissive for myxoma infection in a fashion intimately tied to the activation state of Akt kinase. A host range factor of myxoma virus, M-T5, directly interacts with Akt and mediates myxoma virus tumor cell tropism. mTOR is a regulator of cell growth and metabolism downstream of Akt and is specifically inhibited by rapamycin. We report that treatment of nonpermissive human tumor cell lines, which normally restrict myxoma virus replication, with rapamycin dramatically increased virus tropism and spread in vitro. This increased myxoma replication is concomitant with global effects on mTOR signaling, specifically, an increase in Akt kinase. In contrast to the effects on human cancer cells, rapamycin does not increase myxoma virus replication in rabbit cell lines or permissive human tumor cell lines with constitutively active Akt. This indicates that rapamycin increases the oncolytic capacity of myxoma virus for human cancer cells by reconfiguring the internal cell signaling environment to one that is optimal for productive virus replication and suggests the possibility of a potentially therapeutic synergism between kinase signaling inhibitors and oncolytic poxviruses for cancer treatment.

  20. Suppression of Oncolytic Adenovirus-Mediated Hepatotoxicity by Liver-Specific Inhibition of NF-κB

    Directory of Open Access Journals (Sweden)

    Mitsuhiro Machitani

    2017-12-01

    Full Text Available Telomerase-specific replication-competent adenoviruses (Ads, i.e., TRADs, which possess an E1 gene expression cassette driven by the human telomerase reverse transcriptase promoter, are promising agents for cancer treatment. However, even though oncolytic Ads, including TRAD, are intratumorally administered, they are disseminated from the tumor to systemic circulation, causing concern about oncolytic Ad-mediated hepatotoxicity (due mainly to leaky expression of Ad genes in liver. We reported that inhibition of nuclear factor-κB (NF-κB leads to the suppression of replication-incompetent Ad vector-mediated hepatotoxicity via reduction of the leaky expression of Ad genes in liver. Here, to develop a TRAD with an improved safety profile, we designed a TRAD that carries a liver-specific promoter-driven dominant-negative IκBα (DNIκBα expression cassette (TRAD-DNIκBα. Compared with a conventional TRAD, TRAD-DNIκBα showed hepatocyte-specific inhibition of NF-κB signaling and significantly reduced Ad gene expression and replication in the normal human hepatocyte cell line. TRAD-induced hepatotoxicity was largely suppressed in mice following intravenous administration of TRAD-DNIκBα. However, the replication profiles and oncolytic activities of TRAD-DNIκBα were comparable with those of the conventional TRAD in human non-hepatic tumor cells. These results indicate that oncolytic Ads containing the liver-specific DNIκBα expression cassette have improved safety profiles without inhibiting oncolytic activities.

  1. The combination of i-leader truncation and gemcitabine improves oncolytic adenovirus efficacy in an immunocompetent model.

    Science.gov (United States)

    Puig-Saus, C; Laborda, E; Rodríguez-García, A; Cascalló, M; Moreno, R; Alemany, R

    2014-02-01

    Adenovirus (Ad) i-leader protein is a small protein of unknown function. The C-terminus truncation of the i-leader protein increases Ad release from infected cells and cytotoxicity. In the current study, we use the i-leader truncation to enhance the potency of an oncolytic Ad. In vitro, an i-leader truncated oncolytic Ad is released faster to the supernatant of infected cells, generates larger plaques, and is more cytotoxic in both human and Syrian hamster cell lines. In mice bearing human tumor xenografts, the i-leader truncation enhances oncolytic efficacy. However, in a Syrian hamster pancreatic tumor model, which is immunocompetent and less permissive to human Ad, antitumor efficacy is only observed when the i-leader truncated oncolytic Ad, but not the non-truncated version, is combined with gemcitabine. This synergistic effect observed in the Syrian hamster model was not seen in vitro or in immunodeficient mice bearing the same pancreatic hamster tumors, suggesting a role of the immune system in this synergism. These results highlight the interest of the i-leader C-terminus truncation because it enhances the antitumor potency of an oncolytic Ad and provides synergistic effects with gemcitabine in the presence of an immune competent system.

  2. Patient-derived mesenchymal stem cells as delivery vehicles for oncolytic virotherapy: novel state-of-the-art technology.

    Science.gov (United States)

    Ramírez, Manuel; García-Castro, Javier; Melen, Gustavo J; González-Murillo, África; Franco-Luzón, Lidia

    2015-01-01

    Oncolytic virotherapy is gaining interest in the clinic as a new weapon against cancer. In vivo administration of oncolytic viruses showed important limitations that decrease their effectiveness very significantly: the antiviral immune response causes the elimination of the therapeutic effect, and the poor natural ability of oncolytic viruses to infect micrometastatic lesions significantly minimizes the effective dose of virus. This review will focus on updating the technical and scientific foundations of one of the strategies developed to overcome these limitations, ie, using cells as vehicles for oncolytic viruses. Among many candidates, a special type of adult stem cell, mesenchymal stem cells (MSCs), have already been used in the clinic as cell vehicles for oncolytic viruses, partly due to the fact that these cells are actively being evaluated for other indications. MSC carrier cells are used as Trojan horses loaded with oncoviruses, are administered systemically, and release their cargos at the right places. MSCs are equipped with an array of molecules involved in cell arrest in the capillaries (integrins and selectins), migration toward specific parenchymal locations within tissues (chemokine receptors), and invasion and degradation of the extracellular matrix (proteases). In addition to anatomical targeting capacity, MSCs have a well-recognized role in modulating immune responses by affecting cells of the innate (antigen-presenting cells, natural killer cells) and adaptive immune system (effector and regulatory lymphocytes). Therefore, carrier MSCs may also modulate the immune responses taking place after therapy, ie, the antiviral and the antitumor immune responses.

  3. Changes in Susceptibility to Oncolytic Vesicular Stomatitis Virus during Progression of Prostate Cancer.

    Science.gov (United States)

    Yu, Nanmeng; Puckett, Shelby; Antinozzi, Peter A; Cramer, Scott D; Lyles, Douglas S

    2015-05-01

    A major challenge to oncolytic virus therapy is that individual cancers vary in their sensitivity to oncolytic viruses, even when these cancers arise from the same tissue type. Variability in response may arise due to differences in the initial genetic lesions leading to cancer development. Alternatively, susceptibility to viral oncolysis may change during cancer progression. These hypotheses were tested using cells from a transgenic mouse model of prostate cancer infected with vesicular stomatitis virus (VSV). Primary cultures from murine cancers derived from prostate-specific Pten deletion contained a mixture of cells that were susceptible and resistant to VSV. Castration-resistant cancers contained a higher percentage of susceptible cells than cancers from noncastrated mice. These results indicate both susceptible and resistant cells can evolve within the same tumor. The role of Pten deletion was further investigated using clonal populations of murine prostate epithelial (MPE) progenitor cells and tumor-derived Pten(-/-) cells. Deletion of Pten in MPE progenitor cells using a lentivirus vector resulted in cells that responded poorly to interferon and were susceptible to VSV infection. In contrast, tumor-derived Pten(-/-) cells expressed higher levels of the antiviral transcription factor STAT1, activated STAT1 in response to VSV, and were resistant to VSV infection. These results suggest that early in tumor development following Pten deletion, cells are primarily sensitive to VSV, but subsequent evolution in tumors leads to development of cells that are resistant to VSV infection. Further evolution in castration-resistant tumors leads to tumors in which cells are primarily sensitive to VSV. There has been a great deal of progress in the development of replication-competent viruses that kill cancer cells (oncolytic viruses). However, a major problem is that individual cancers vary in their sensitivity to oncolytic viruses, even when these cancers arise from the

  4. Recombination of Globally Circulating Varicella-Zoster Virus.

    Science.gov (United States)

    Norberg, Peter; Depledge, Daniel P; Kundu, Samit; Atkinson, Claire; Brown, Julianne; Haque, Tanzina; Hussaini, Yusuf; MacMahon, Eithne; Molyneaux, Pamela; Papaevangelou, Vassiliki; Sengupta, Nitu; Koay, Evelyn S C; Tang, Julian W; Underhill, Gillian S; Grahn, Anna; Studahl, Marie; Breuer, Judith; Bergström, Tomas

    2015-07-01

    Varicella-zoster virus (VZV) is a human herpesvirus, which during primary infection typically causes varicella (chicken pox) and establishes lifelong latency in sensory and autonomic ganglia. Later in life, the virus may reactivate to cause herpes zoster (HZ; also known as shingles). To prevent these diseases, a live-attenuated heterogeneous vaccine preparation, vOka, is used routinely in many countries worldwide. Recent studies of another alphaherpes virus, infectious laryngotracheitis virus, demonstrate that live-attenuated vaccine strains can recombine in vivo, creating virulent progeny. These findings raised concerns about using attenuated herpesvirus vaccines under conditions that favor recombination. To investigate whether VZV may undergo recombination, which is a prerequisite for VZV vaccination to create such conditions, we here analyzed 115 complete VZV genomes. Our results demonstrate that recombination occurs frequently for VZV. It thus seems that VZV is fully capable of recombination if given the opportunity, which may have important implications for continued VZV vaccination. Although no interclade vaccine wild-type recombinant strains were found, intraclade recombinants were frequently detected in clade 2, which harbors the vaccine strains, suggesting that the vaccine strains have already been involved in recombination events, either in vivo or in vitro during passages in cell culture. Finally, previous partial and complete genomic studies have described strains that do not cluster phylogenetically to any of the five established clades. The additional VZV strains sequenced here, in combination with those previously published, have enabled us to formally define a novel sixth VZV clade. Although genetic recombination has been demonstrated to frequently occur for other human alphaherpesviruses, herpes simplex viruses 1 and 2, only a few ancient and isolated recent recombination events have hitherto been demonstrated for VZV. In the present study, we

  5. VEGF-Mediated Induction of PRD1-BF1/Blimp1 Expression Sensitizes Tumor Vasculature to Oncolytic Virus Infection.

    Science.gov (United States)

    Arulanandam, Rozanne; Batenchuk, Cory; Angarita, Fernando A; Ottolino-Perry, Kathryn; Cousineau, Sophie; Mottashed, Amelia; Burgess, Emma; Falls, Theresa J; De Silva, Naomi; Tsang, Jovian; Howe, Grant A; Bourgeois-Daigneault, Marie-Claude; Conrad, David P; Daneshmand, Manijeh; Breitbach, Caroline J; Kirn, David H; Raptis, Leda; Sad, Subash; Atkins, Harold; Huh, Michael S; Diallo, Jean-Simon; Lichty, Brian D; Ilkow, Carolina S; Le Boeuf, Fabrice; Addison, Christina L; McCart, J Andrea; Bell, John C

    2015-08-10

    Oncolytic viruses designed to attack malignant cells can in addition infect and destroy tumor vascular endothelial cells. We show here that this expanded tropism of oncolytic vaccinia virus to the endothelial compartment is a consequence of VEGF-mediated suppression of the intrinsic antiviral response. VEGF/VEGFR2 signaling through Erk1/2 and Stat3 leads to upregulation, nuclear localization, and activation of the transcription repressor PRD1-BF1/Blimp1. PRD1-BF1 does not contribute to the mitogenic effects of VEGF, but directly represses genes involved in type I interferon (IFN)-mediated antiviral signaling. In vivo suppression of VEGF signaling diminishes PRD1-BF1/Blimp1 expression in tumor vasculature and inhibits intravenously administered oncolytic vaccinia delivery to and consequent spread within the tumor. Copyright © 2015 Elsevier Inc. All rights reserved.

  6. Sorting out Pandora’s box: discerning the dynamic roles of liver microenvironment in oncolytic virus therapy for hepatocellular carcinoma

    Directory of Open Access Journals (Sweden)

    Oliver eEbert

    2014-04-01

    Full Text Available Oncolytic viral therapies have recently found their way into clinical application for hepatocellular carcinoma (HCC, a disease with limited treatment options and poor prognosis. Adding to the many intrinsic challenges of in vivo oncolytic viral therapy, is the complex microenvironment of the liver, which imposes unique limitations to the successful delivery and propagation of the virus. The normal liver milieu is characterized by an intricate network of hepatocytes and non-parenchymal cells including Kupffer cells, stellate cells, and sinusoidal endothelial cells, which can secrete antiviral cytokines, provide a platform for non-specific uptake, and form a barrier to efficient viral spread. In addition, NK cells are greatly enriched in the liver, contributing to the innate defense against viruses. The situation is further complicated when HCC arises in the setting of underlying hepatitis virus infection and/or hepatic cirrhosis, which occurs in more than 90% of clinical cases. These conditions pose further inhibitory effects on oncolytic virus therapy due to the presence of chronic inflammation, constitutive cytokine expression, altered hepatic blood flow, and extracellular matrix deposition. In addition, oncolytic viruses can modulate the hepatic microenvironment, resulting in a complex interplay between virus and host. The immune system undoubtedly plays a substantial role in the outcome of oncolytic virus therapy, both as an inhibitor of viral replication, and as a potent mechanism of virus-mediated tumor cell killing. This review will discuss the particular challenges of oncolytic viral therapy for HCC, as well as some potential strategies for modulating the immune system and synergizing with the hepatic microenvironment to improve therapeutic outcome. 

  7. Patient-derived mesenchymal stem cells as delivery vehicles for oncolytic virotherapy: novel state-of-the-art technology

    Directory of Open Access Journals (Sweden)

    Ramírez M

    2015-10-01

    Full Text Available Manuel Ramírez,1 Javier García-Castro,2 Gustavo J Melen,1 África González-Murillo,1 Lidia Franco-Luzón1 1Oncohematología, Hospital Universitario Niño Jesús, 2Unidad de Biotecnología Celular, Instituto de Salud Carlos III, Madrid, Spain Abstract: Oncolytic virotherapy is gaining interest in the clinic as a new weapon against cancer. In vivo administration of oncolytic viruses showed important limitations that decrease their effectiveness very significantly: the antiviral immune response causes the elimination of the therapeutic effect, and the poor natural ability of oncolytic viruses to infect micrometastatic lesions significantly minimizes the effective dose of virus. This review will focus on updating the technical and scientific foundations of one of the strategies developed to overcome these limitations, ie, using cells as vehicles for oncolytic viruses. Among many candidates, a special type of adult stem cell, mesenchymal stem cells (MSCs, have already been used in the clinic as cell vehicles for oncolytic viruses, partly due to the fact that these cells are actively being evaluated for other indications. MSC carrier cells are used as Trojan horses loaded with oncoviruses, are administered systemically, and release their cargos at the right places. MSCs are equipped with an array of molecules involved in cell arrest in the capillaries (integrins and selectins, migration toward specific parenchymal locations within tissues (chemokine receptors, and invasion and degradation of the extracellular matrix (proteases. In addition to anatomical targeting capacity, MSCs have a well-recognized role in modulating immune responses by affecting cells of the innate (antigen-presenting cells, natural killer cells and adaptive immune system (effector and regulatory lymphocytes. Therefore, carrier MSCs may also modulate the immune responses taking place after therapy, ie, the antiviral and the antitumor immune responses. Keywords: virotherapy

  8. Therapeutic Recombinant Monoclonal Antibodies

    Science.gov (United States)

    Bakhtiar, Ray

    2012-01-01

    During the last two decades, the rapid growth of biotechnology-derived techniques has led to a myriad of therapeutic recombinant monoclonal antibodies with significant clinical benefits. Recombinant monoclonal antibodies can be obtained from a number of natural sources such as animal cell cultures using recombinant DNA engineering. In contrast to…

  9. M011L-deficient oncolytic myxoma virus induces apoptosis in brain tumor-initiating cells and enhances survival in a novel immunocompetent mouse model of glioblastoma.

    Science.gov (United States)

    Pisklakova, Alexandra; McKenzie, Brienne; Zemp, Franz; Lun, Xueqing; Kenchappa, Rajappa S; Etame, Arnold B; Rahman, Masmudur M; Reilly, Karlyne; Pilon-Thomas, Shari; McFadden, Grant; Kurz, Ebba; Forsyth, Peter A

    2016-03-08

    Myxoma virus (MYXV) is a promising oncolytic agent and is highly effective against immortalized glioma cells but less effective against brain tumor initiating cells (BTICs), which are believed to mediate glioma development/recurrence. MYXV encodes various proteins to attenuate host cell apoptosis, including an antiapoptotic Bcl-2 homologue known as M011L. Such proteins may limit the ability of MYXV to kill BTICs, which have heightened resistance to apoptosis. We hypothesized that infecting BTICs with an M011L-deficient MYXV construct would overcome BTIC resistance to MYXV. We used patient-derived BTICs to evaluate the efficacy of M011L knockout virus (vMyx-M011L-KO) versus wild-type MYXV (vMyx-WT) and characterized the mechanism of virus-induced cell death in vitro. To extend our findings in a novel immunocompetent animal model, we derived, cultured, and characterized a C57Bl/6J murine BTIC (mBTIC0309) from a spontaneous murine glioma and evaluated vMyx-M011L-KO efficacy with and without temozolomide (TMZ) in mBTIC0309-bearing mice. We demonstrated that vMyx-M011L-KO induces apoptosis in BTICs, dramatically increasing sensitivity to the virus. vMyx-WT failed to induce apoptosis as M011L protein prevented Bax activation and cytochrome c release. In vivo, intracranial implantation of mBTIC0309 generated tumors that closely recapitulated the pathological and molecular profile of human gliomas. Treatment of tumor-bearing mice with vMyx-M011L-KO significantly prolonged survival in immunocompetent-but not immunodeficient-mouse models, an effect that is significantly enhanced in combination with TMZ. Our data suggest that vMyx-M011L-KO is an effective, well-tolerated, proapoptotic oncolytic virus and a strong candidate for clinical translation. © The Author(s) 2016. Published by Oxford University Press on behalf of the Society for Neuro-Oncology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  10. Mutations in the glycoprotein of vesicular stomatitis virus affect cytopathogenicity: potential for oncolytic virotherapy.

    Science.gov (United States)

    Janelle, Valérie; Brassard, Frédérick; Lapierre, Pascal; Lamarre, Alain; Poliquin, Laurent

    2011-07-01

    Vesicular stomatitis virus (VSV) has been widely used to characterize cellular processes, viral resistance, and cytopathogenicity. Recently, VSV has also been used for oncolytic virotherapy due to its capacity to selectively lyse tumor cells. Mutants of the matrix (M) protein of VSV have generally been preferred to the wild-type virus for oncolysis because of their ability to induce type I interferon (IFN) despite causing weaker cytopathic effects. However, due to the large variability of tumor types, it is quite clear that various approaches and combinations of multiple oncolytic viruses will be needed to effectively treat most cancers. With this in mind, our work focused on characterizing the cytopathogenic profiles of four replicative envelope glycoprotein (G) VSV mutants. In contrast to the prototypic M mutant, VSV G mutants are as efficient as wild-type virus at inhibiting cellular transcription and host protein translation. Despite being highly cytopathic, the mutant G(6R) triggers type I interferon secretion as efficiently as the M mutant. Importantly, most VSV G mutants are more effective at killing B16 and MC57 tumor cells in vitro than the M mutant or wild-type virus through apoptosis induction. Taken together, our results demonstrate that VSV G mutants retain the high cytopathogenicity of wild-type VSV, with G(6R) inducing type I IFN secretion at levels similar to that of the M mutant. VSV G protein mutants could therefore prove to be highly valuable for the development of novel oncolytic virotherapy strategies that are both safe and efficient for the treatment of various types of cancer.

  11. Interference of CD40L-mediated tumor immunotherapy by oncolytic vesicular stomatitis virus.

    Science.gov (United States)

    Galivo, Feorillo; Diaz, Rosa Maria; Thanarajasingam, Uma; Jevremovic, Dragan; Wongthida, Phonphimon; Thompson, Jill; Kottke, Timothy; Barber, Glen N; Melcher, Alan; Vile, Richard G

    2010-04-01

    Oncolytic virotherapy can be achieved in two ways: (1) by exploiting an innate ability of certain viruses to selectively replicate in tumor tissues, and (2) by using viruses to deliver toxic or immunostimulatory genes to tumors. Vesicular stomatitis virus (VSV) selectively replicates in tumors lacking adequate type I interferon response. The efficacy of oncolytic virotherapy using VSV against B16 melanomas in C57BL/6 mice is dependent on CD8(+) T and natural killer cells. Because immunotherapies that prime specific CD8(+) T cells against melanocyte/melanoma antigens can generate significant therapeutic responses, we hypothesized that engineering VSV to express the potent T cell costimulatory molecule CD40 ligand (VSV-CD40L) would enhance virotherapy with concomitant priming of melanoma-specific T cells. However, we observed no difference in antitumor efficacy between the parental VSV-GFP and VSV-CD40L. In contrast, intratumoral injection of a replication-defective adenovirus expressing CD40L (Ad-CD40L) consistently produced significantly greater therapy than either replication-competent VSV-GFP or VSV-CD40L. The Ad-CD40L-mediated tumor regressions were associated with specific T cell responses against tumor-associated antigens (TAAs), which took several days to develop, whereas VSV-CD40L rapidly induced high levels of T cell activation without specificity for TAAs. These data suggest that the high levels of VSV-associated immunogenicity distracted immune responses away from priming of tumor-specific T cells, even in the presence of potent costimulatory signals. In contrast, a replication-defective Ad-CD40L allowed significant priming of T cells directed against TAAs. These observations suggest that an efficiently primed antitumor T cell response can produce similar, if not better, therapy against an established melanoma compared with intratumoral injection of a replication-competent oncolytic virus.

  12. Characteristics of oncolytic vesicular stomatitis virus displaying tumor-targeting ligands.

    Science.gov (United States)

    Ammayappan, Arun; Peng, Kah-Whye; Russell, Stephen J

    2013-12-01

    We sought proof of principle that tumor-targeting ligands can be displayed on the surface of vesicular stomatitis virus (VSV) by engineering its glycoprotein. Here, we successfully rescued VSVs displaying tumor vasculature-targeting ligands. By using a rational approach, we investigated various feasible insertion sites on the G protein of VSV (VSV-G) for display of tumor vasculature-targeting ligands, cyclic RGD (cRGD) and echistatin. We found seven sites on VSV-G that tolerated insertion of the 9-residue cRGD peptide, two of which could tolerate insertion of the 49-amino acid echistatin domain. All of the ligand-displaying viruses replicated as well as the parental virus. In vitro studies demonstrated that the VSV-echistatin viruses specifically bound to targeted integrins. Since the low-density lipoprotein receptor (LDLR) was recently identified as a major receptor for VSV, we investigated the entry of ligand-displaying viruses after masking LDLR. The experiment showed that the modified viruses can enter the cell independently of LDLR, whereas entry of unmodified virus is significantly blocked by a specific monoclonal antibody against LDLR. Both parental and ligand-displaying viruses displayed equal oncolytic efficacies in a syngeneic mouse myeloma model. We further demonstrated that single-chain antibody fragments against tumor-specific antigens can be inserted at the N terminus of the G protein and that corresponding replication-competent VSVs can be rescued efficiently. Overall, we demonstrated that functional tumor-targeting ligands can be displayed on replication-competent VSVs without perturbing viral growth and oncolytic efficacy. This study provides a rational foundation for the future development of fully retargeted oncolytic VSVs.

  13. Myxoma virus oncolytic efficiency can be enhanced through chemical or genetic disruption of the actin cytoskeleton.

    Directory of Open Access Journals (Sweden)

    Chad R Irwin

    Full Text Available Myxoma virus (MYXV is one of many animal viruses that exhibit oncolytic properties in transformed human cells. Compared to orthopoxviruses like vaccinia (VACV, MYXV spreads inefficiently, which could compromise its use in treating tumors and their associated metastases. The VACV F11 protein promotes virus exit and rapid spread by inhibiting Rho signalling, which results in a disruption of cortical actin. We have previously shown that although MYXV lacks an F11 homolog, the F11L gene can be introduced into MYXV promoting the spread of this Leporipoxvirus in natural host cells. Here we show that the F11-encoding (F11L(+ MYXV strain replicates to higher levels in a number of human cancer cells. We also show that F11L(+ MYXV induces better tumor control and prolonged survival of mice bearing MDA-MB-231 cancer cells. Furthermore, we show that this virus also spreads more efficiently from the site of growth in one injected tumor, to a second untreated tumor. While we focused mostly on the use of a modified MYXV we were able to show that the effects of F11 on MYXV growth in cancer cells could be mimicked through the use of pharmacological inhibition or siRNA-mediated silencing of key regulators of cortical actin (RhoA, RhoC, mDia1, or LIMK2. These data suggest that it may be possible to increase the oncolytic efficacy of wild-type MYXV using chemical inhibitors of RhoA/C or their downstream targets. Furthermore, since all viruses must overcome barriers to exit posed by structures like cortical actin, these findings suggest that the oncolytic activity of other viruses may be enhanced through similar strategies.

  14. Myxoma Virus Oncolytic Efficiency Can Be Enhanced Through Chemical or Genetic Disruption of the Actin Cytoskeleton

    Science.gov (United States)

    Irwin, Chad R.; Favis, Nicole A.; Agopsowicz, Kate C.; Hitt, Mary M.; Evans, David H.

    2013-01-01

    Myxoma virus (MYXV) is one of many animal viruses that exhibit oncolytic properties in transformed human cells. Compared to orthopoxviruses like vaccinia (VACV), MYXV spreads inefficiently, which could compromise its use in treating tumors and their associated metastases. The VACV F11 protein promotes virus exit and rapid spread by inhibiting Rho signalling, which results in a disruption of cortical actin. We have previously shown that although MYXV lacks an F11 homolog, the F11L gene can be introduced into MYXV promoting the spread of this Leporipoxvirus in natural host cells. Here we show that the F11-encoding (F11L+) MYXV strain replicates to higher levels in a number of human cancer cells. We also show that F11L+ MYXV induces better tumor control and prolonged survival of mice bearing MDA-MB-231 cancer cells. Furthermore, we show that this virus also spreads more efficiently from the site of growth in one injected tumor, to a second untreated tumor. While we focused mostly on the use of a modified MYXV we were able to show that the effects of F11 on MYXV growth in cancer cells could be mimicked through the use of pharmacological inhibition or siRNA-mediated silencing of key regulators of cortical actin (RhoA, RhoC, mDia1, or LIMK2). These data suggest that it may be possible to increase the oncolytic efficacy of wild-type MYXV using chemical inhibitors of RhoA/C or their downstream targets. Furthermore, since all viruses must overcome barriers to exit posed by structures like cortical actin, these findings suggest that the oncolytic activity of other viruses may be enhanced through similar strategies. PMID:24391902

  15. Efficacy of oncolytic adenovirus expressing suicide genes and interleukin-12 in preclinical model of prostate cancer.

    Science.gov (United States)

    Freytag, S O; Barton, K N; Zhang, Y

    2013-12-01

    Oncolytic adenovirus-mediated suicide gene therapy has been shown to improve local tumor control in preclinical tumor models and in the clinic. Although local tumor control is important, for most human cancers, new therapies must also target metastatic disease if they are to have an impact on survival. Here, we test the hypothesis that adding cytokine gene therapy to our multimodal platform improves both local and metastatic tumor control in a preclinical model of prostate cancer. An oncolytic adenovirus (Ad5-yCD/mutTKSR39rep-mIL12) expressing two suicide genes and mouse interleukin-12 (IL-12) was generated. Relative to an adenovirus lacking IL-12 (Ad5-yCD/mutTKSR39rep), Ad5-yCD/mutTKSR39rep-mIL12 improved local and metastatic tumor control in the TRAMP-C2 prostate adenocarcinoma model, resulting in a significant increase in survival. Ad5-yCD/mutTKSR39rep-mIL12 resulted in high levels of IL-12 and interferon gamma in serum and tumor, increased natural killer (NK) and cytotoxic T-lymphocyte lytic activities, and the development of tumor-specific antitumor immunity. Immune cell depletion studies indicated that both the innate and adaptive arms of immunity were required for maximal Ad5-yCD/mutTKSR39rep-mIL12 activity. The results demonstrate that the addition of IL-12 significantly improves the efficacy of oncolytic adenovirus-mediated suicide gene therapy and provide the scientific basis for future trials targeting locally aggressive cancers.

  16. Treatment of orthotopic malignant peripheral nerve sheath tumors with oncolytic herpes simplex virus.

    Science.gov (United States)

    Antoszczyk, Slawomir; Spyra, Melanie; Mautner, Victor Felix; Kurtz, Andreas; Stemmer-Rachamimov, Anat O; Martuza, Robert L; Rabkin, Samuel D

    2014-08-01

    Malignant peripheral nerve sheath tumors (MPNSTs) are an aggressive and often lethal sarcoma that frequently develops in patients with neurofibromatosis type 1 (NF1). We developed new preclinical MPNST models and tested the efficacy of oncolytic herpes simplex viruses (oHSVs), a promising cancer therapeutic that selectively replicates in and kills cancer cells. Mouse NF1(-) MPNST cell lines and human NF1(-) MPNST stemlike cells (MSLCs) were implanted into the sciatic nerves of immunocompetent and athymic mice, respectively. Tumor growth was followed by external measurement and sciatic nerve deficit using a hind-limb scoring system. Oncolytic HSV G47Δ as well as "armed" G47Δ expressing platelet factor 4 (PF4) or interleukin (IL)-12 were injected intratumorally into established sciatic nerve tumors. Mouse MPNST cell lines formed tumors with varying growth kinetics. A single intratumoral injection of G47Δ in sciatic nerve tumors derived from human S462 MSLCs in athymic mice or mouse M2 (37-3-18-4) cells in immunocompetent mice significantly inhibited tumor growth and prolonged survival. Local IL-12 expression significantly improved the efficacy of G47Δ in syngeneic mice, while PF4 expression prolonged survival. Injection of G47Δ directly into the sciatic nerve of athymic mice resulted in only mild symptoms that did not differ from phosphate buffered saline control. Two new orthotopic MPNST models are described, including in syngeneic mice, expanding the options for preclinical testing. Oncolytic HSV G47Δ exhibited robust efficacy in both immunodeficient and immunocompetent MPNST models while maintaining safety. Interleukin-12 expression improved efficacy. These studies support the clinical translation of G47Δ for patients with MPNST. © The Author(s) 2014. Published by Oxford University Press on behalf of the Society for Neuro-Oncology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  17. Oncolytic viruses for cancer therapy I. Cell-external factors: virus entry and receptor interaction.

    Science.gov (United States)

    Campbell, Stephanie A; Gromeier, Matthias

    2005-03-01

    After being recognized for their anti-neoplastic properties at the beginning of the last century, viruses are again being considered for use as therapeutic agents against cancer. Certain virus species have a propensity to replicate within transformed cells, which are commonly rendered vulnerable due to tumor-specific defects in their defense against viral infection. Other viruses have been modified to subject them to tumor-specific growth conditions. Oncolytic viruses carry the promise to efficiently target cancer cells for destruction and spread throughout tumor tissue to reach distant neoplastic loci without causing collateral damage to healthy tissues. In contrast to conventional cancer chemotherapy, viral anti-neoplastic agents require complex interactions with the host organism to reach their target and to unfold their oncolytic activity. Recent progress in the elucidation of the molecular mechanisms of viral pathogenesis has opened up new opportunities to manipulate virus-host interactions, generating effective anti-tumor strategies. On the other hand, significant obstacles towards the application of safe and efficacious viral therapies have become apparent. These frequently relate to the lack of cell culture and animal tumor models that accurately reflect the characteristics of cancerous tissues in patients. Throughout the past century, viral therapeutics against cancer have evolved into a new class of treatment strategies characterized by unique opportunities and challenges. A growing number of oncolytic viruses has entered clinical investigation or is scheduled to do so in the near future. Great efforts are being undertaken to rekindle an old idea and, with the help of new technologies, to realize its promise of new treatment facilities for cancer.

  18. Preclinical toxicology of oncolytic adenovirus-mediated cytotoxic and interleukin-12 gene therapy for prostate cancer

    Directory of Open Access Journals (Sweden)

    Svend O Freytag

    Full Text Available The purpose of this study was to examine the toxicity of combining oncolytic adenovirus-mediated cytotoxic and interleukin 12 (IL-12 gene therapy in a preclinical model to support future phase 1 trials. One hundred and twenty C57BL/6 male mice received an intraprostatic injection of saline (n = 24 or an oncolytic adenovirus (Ad5-yCD/mutTKSR39rep-mIL12 expressing two suicide genes and mouse IL-12 (n = 96. The adenovirus was administered at three dose levels (1.3 × 106, 1.3 × 107, 1.3 × 108 vp/kg followed by 2 weeks of 5-flurocytosine (5-FC and gancliclovir (GCV prodrug therapy. There were no premature deaths. Daily observations of animals did not reveal any obvious clinical problems throughout the 78-day in-life phase of the study. Animals in the highest adenovirus dose group exhibited lymphopenia and transaminitis on day 3, both of which resolved by day 17. Except for mild inflammation of the prostate and seminal vesicles, histopathology of major organs was largely unremarkable. IL-12 and interferon-gamma levels in prostate and serum peaked on day 3 and were either undetectable or returned to baseline levels by day 17. No adenoviral DNA was detected in serum in any group at any time point. The results demonstrate that local administration of an oncolytic adenovirus expressing two suicide genes and IL-12 is well tolerated and support moving this investigational approach into human trials.

  19. Oncolytic Adenovirus and Tumor-Targeting Immune Modulatory Therapy Improve Autologous Cancer Vaccination.

    Science.gov (United States)

    Jiang, Hong; Rivera-Molina, Yisel; Gomez-Manzano, Candelaria; Clise-Dwyer, Karen; Bover, Laura; Vence, Luis M; Yuan, Ying; Lang, Frederick F; Toniatti, Carlo; Hossain, Mohammad B; Fueyo, Juan

    2017-07-15

    Oncolytic viruses selectively lyse tumor cells, disrupt immunosuppression within the tumor, and reactivate antitumor immunity, but they have yet to live up to their therapeutic potential. Immune checkpoint modulation has been efficacious in a variety of cancer with an immunogenic microenvironment, but is associated with toxicity due to nonspecific T-cell activation. Therefore, combining these two strategies would likely result in both effective and specific cancer therapy. To test the hypothesis, we first constructed oncolytic adenovirus Delta-24-RGDOX expressing the immune costimulator OX40 ligand (OX40L). Like its predecessor Delta-24-RGD, Delta-24-RGDOX induced immunogenic cell death and recruit lymphocytes to the tumor site. Compared with Delta-24-RGD, Delta-24-RGDOX exhibited superior tumor-specific activation of lymphocytes and proliferation of CD8+ T cells specific to tumor-associated antigens, resulting in cancer-specific immunity. Delta-24-RGDOX mediated more potent antiglioma activity in immunocompetent C57BL/6 but not immunodeficient athymic mice, leading to specific immune memory against the tumor. To further overcome the immune suppression mediated by programmed death-ligand 1 (PD-L1) expression on cancer cells accompanied with virotherapy, intratumoral injection of Delta-24-RGDOX and an anti-PD-L1 antibody showed synergistic inhibition of gliomas and significantly increased survival in mice. Our data demonstrate that combining an oncolytic virus with tumor-targeting immune checkpoint modulators elicits potent in situ autologous cancer vaccination, resulting in an efficacious, tumor-specific, and long-lasting therapeutic effect. Cancer Res; 77(14); 3894-907. ©2017 AACR. ©2017 American Association for Cancer Research.

  20. Cellular factors promoting resistance to effective treatment of glioma with oncolytic myxoma virus.

    Science.gov (United States)

    Zemp, Franz J; McKenzie, Brienne A; Lun, Xueqing; Reilly, Karlyne M; McFadden, Grant; Yong, V Wee; Forsyth, Peter A

    2014-12-15

    Oncolytic virus therapy is being evaluated in clinical trials for human glioma. While it is widely assumed that the immune response of the patient to the virus infection limits the utility of the therapy, investigations into the specific cell type(s) involved in this response have been performed using nonspecific pharmacologic inhibitors or allogeneic models with compromised immunity. To identify the immune cells that participate in clearing an oncolytic infection in glioma, we used flow cytometry and immunohistochemistry to immunophenotype an orthotopic glioma model in immunocompetent mice after Myxoma virus (MYXV) administration. These studies revealed a large resident microglia and macrophage population in untreated tumors, and robust monocyte, T-, and NK cell infiltration 3 days after MYXV infection. To determine the role on the clinical utility of MYXV therapy for glioma, we used a combination of knockout mouse strains and specific immunocyte ablation techniques. Collectively, our experiments identify an important role for tumor-resident myeloid cells and overlapping roles for recruited NK and T cells in the clearance and efficacy of oncolytic MYXV from gliomas. Using a cyclophosphamide regimen to achieve lymphoablation prior and during MYXV treatment, we prevented treatment-induced peripheral immunocyte recruitment and, surprisingly, largely ablated the tumor-resident macrophage population. Virotherapy of cyclophosphamide-treated animals resulted in sustained viral infection within the glioma as well as a substantial survival advantage. This study demonstrates that resistance to MYXV virotherapy in syngeneic glioma models involves a multifaceted cellular immune response that can be overcome with cyclophosphamide-mediated lymphoablation. ©2014 American Association for Cancer Research.

  1. Myxoma virus oncolytic efficiency can be enhanced through chemical or genetic disruption of the actin cytoskeleton.

    Science.gov (United States)

    Irwin, Chad R; Favis, Nicole A; Agopsowicz, Kate C; Hitt, Mary M; Evans, David H

    2013-01-01

    Myxoma virus (MYXV) is one of many animal viruses that exhibit oncolytic properties in transformed human cells. Compared to orthopoxviruses like vaccinia (VACV), MYXV spreads inefficiently, which could compromise its use in treating tumors and their associated metastases. The VACV F11 protein promotes virus exit and rapid spread by inhibiting Rho signalling, which results in a disruption of cortical actin. We have previously shown that although MYXV lacks an F11 homolog, the F11L gene can be introduced into MYXV promoting the spread of this Leporipoxvirus in natural host cells. Here we show that the F11-encoding (F11L(+)) MYXV strain replicates to higher levels in a number of human cancer cells. We also show that F11L(+) MYXV induces better tumor control and prolonged survival of mice bearing MDA-MB-231 cancer cells. Furthermore, we show that this virus also spreads more efficiently from the site of growth in one injected tumor, to a second untreated tumor. While we focused mostly on the use of a modified MYXV we were able to show that the effects of F11 on MYXV growth in cancer cells could be mimicked through the use of pharmacological inhibition or siRNA-mediated silencing of key regulators of cortical actin (RhoA, RhoC, mDia1, or LIMK2). These data suggest that it may be possible to increase the oncolytic efficacy of wild-type MYXV using chemical inhibitors of RhoA/C or their downstream targets. Furthermore, since all viruses must overcome barriers to exit posed by structures like cortical actin, these findings suggest that the oncolytic activity of other viruses may be enhanced through similar strategies.

  2. Myxoma virus is a novel oncolytic virus with significant antitumor activity against experimental human gliomas.

    Science.gov (United States)

    Lun, Xueqing; Yang, Wenqing; Alain, Tommy; Shi, Zhong-Qiao; Muzik, Huong; Barrett, John W; McFadden, Grant; Bell, John; Hamilton, Mark G; Senger, Donna L; Forsyth, Peter A

    2005-11-01

    Myxoma virus, a poxvirus previously considered rabbit specific, can replicate productively in a variety of human tumor cells in culture. The purpose of this study was to determine if there was efficacy or toxicities of this oncolytic virus against experimental models of human malignant gliomas in vitro, in vivo, and ex vivo in malignant glioma specimens. In vitro, the majority of glioma cell lines tested (7 of 8, 87.5%) were fully permissive for myxoma virus replication and killed by infection. In vivo, intracerebral (i.c.) myxoma virus inoculation was well tolerated and produced only minimal focal inflammatory changes at the site of viral inoculation. U87 and U251 orthotopic xenograft models were used to assess myxoma virus efficacy in vivo. A single intratumoral injection of myxoma virus dramatically prolonged median survival compared with treatment with UV-inactivated myxoma virus. Median survival was not reached in myxoma virus-treated groups versus 47.3 days (U87; P = 0.0002) and 50.7 days (U251; P = 0.0027) in UV-inactivated myxoma virus-treated groups. Most myxoma virus-treated animals (12 of 13, 92%) were alive and apparently "cured" when the experiment was finished (>130 days). Interestingly, we found a selective and long-lived myxoma virus infection in gliomas in vivo. This is the first demonstration of the oncolytic activity of myxoma virus in vivo. The nonpathogenic nature of myxoma virus outside of the rabbit host, its capacity to be genetically modified, its ability to produce a long-lived infection in human tumor cells, and the lack of preexisting antibodies in the human population suggest that myxoma virus may be an attractive oncolytic agent against human malignant glioma.

  3. Molecular Pathways: Mechanism of Action for Talimogene Laherparepvec, a New Oncolytic Virus Immunotherapy.

    Science.gov (United States)

    Kohlhapp, Frederick J; Kaufman, Howard L

    2016-03-01

    Oncolytic viruses are native or engineered viruses that preferentially replicate in and lyse cancer cells. Selective tumor cell replication is thought to depend on infection of neoplastic cells, which harbor low levels of protein kinase R (PKR) and dysfunctional type I IFN signaling elements. These changes allow more efficient viral replication, and with selected deletion of specific viral genes, replication in normal cells with activated PKR may not be possible. Direct tumor cell lysis, release of soluble tumor antigens, and danger-associated molecular factors are all thought to help prime and promote tumor-specific immunity. Talimogene laherparepvec (T-VEC) is a genetically modified herpes simplex virus, type I and is the first oncolytic virus to demonstrate a clinical benefit in patients with melanoma. T-VEC has also been evaluated for the treatment of head and neck cancer, pancreatic cancer, and likely other types of cancer will be targeted in the near future. T-VEC has been modified for improved safety, tumor-selective replication, and induction of host immunity by deletion of several viral genes and expression of human granulocyte-macrophage colony stimulating factor. Although the mechanism of action for T-VEC is incompletely understood, the safety profile of T-VEC and ability to promote immune responses suggest future combination studies with other immunotherapy approaches including checkpoint blockade through PD-1, PD-L1, and CTLA-4 to be a high priority for clinical development. Oncolytic viruses also represent unique regulatory and biosafety challenges but offer a potential new class of agents for the treatment of cancer. ©2015 American Association for Cancer Research.

  4. Oncolytic recombinant vesicular stomatitis virus (VSV) is nonpathogenic and non-transmissible in pigs, a natural host of VSV

    Science.gov (United States)

    Vesicular stomatitis virus (VSV) is a negative stranded RNA virus that naturally causes disease in agricultural livestock including horses, cattle and pigs. The two main identified VSV strains are the New Jersey (VSNJV) and Indiana (VSIV) strains. VSV is a rapidly replicating, potently immunogenic v...

  5. Oncolytic Virotherapy Synergism with Signaling Inhibitors: Rapamycin Increases Myxoma Virus Tropism for Human Tumor Cells▿

    OpenAIRE

    Stanford, Marianne M.; Barrett, John W.; Nazarian, Steven H.; Werden, Steven; McFadden, Grant

    2006-01-01

    Myxoma virus is a rabbit-specific poxvirus pathogen that also exhibits a unique tropism for human tumor cells and is dramatically oncolytic for human cancer xenografts. Most tumor cell lines tested are permissive for myxoma infection in a fashion intimately tied to the activation state of Akt kinase. A host range factor of myxoma virus, M-T5, directly interacts with Akt and mediates myxoma virus tumor cell tropism. mTOR is a regulator of cell growth and metabolism downstream of Akt and is spe...

  6. Development of new therapy for canine mammary cancer with recombinant measles virus

    Directory of Open Access Journals (Sweden)

    Koichiro Shoji

    2016-01-01

    Full Text Available Oncolytic virotherapy is a promising treatment strategy for cancer. We previously generated a recombinant measles virus (rMV-SLAMblind that selectively uses a poliovirus receptor-related 4 (PVRL4/Nectin4 receptor, but not signaling lymphocyte activation molecule (SLAM. We demonstrated that the virus exerts therapeutic effects against human breast cancer cells. Here, we examined the applicability of rMV-SLAMblind to treating canine mammary cancers (CMCs. We found that the susceptibilities of host cells to rMV-SLAMblind were dependent on canine Nectin-4 expression. Nectin-4 was detected in four of nine CMC cell lines. The rMV-SLAMblind efficiently infected those four Nectin-4-positive cell lines and was cytotoxic for three of them (CF33, CHMm, and CTBm. In vivo experiment showed that the administration of rMV-SLAMblind greatly suppressed the progression of tumors in mice xenografted with a CMC cell line (CF33. Immunohistochemistry revealed that canine Nectin-4 was expressed in 45% of canine mammary tumors, and the tumor cells derived from one clinical specimen were efficiently infected with rMV-SLAMblind. These results suggest that rMV-SLAMblind infects CMC cells and displays antitumor activity in vitro, in xenografts, and ex vivo. Therefore, oncolytic virotherapy with rMV-SLAMblind can be a novel method for treating CMCs.

  7. Arming viruses in multi-mechanistic oncolytic viral therapy: current research and future developments, with emphasis on poxviruses

    Directory of Open Access Journals (Sweden)

    Sampath P

    2013-12-01

    Full Text Available Padma Sampath, Steve H ThorneDepartment of Surgery, University of Pittsburgh Cancer Institute, University of Pittsburgh, Pittsburgh, PA, USAAbstract: The field of oncolytic virology has made great strides in recent years. However, one key finding has been that the use of viral agents that replicate selectively in tumors is usually insufficient to achieve anything beyond small and transient responses. Instead, like most cancer therapies, oncolytic viruses are most effective in combination with other therapies, which is where they have proven therapeutic effects in clinical and preclinical studies. In cases of some of the smaller RNA viruses, effects can only be achieved through combination regimens with chemotherapy, radiotherapy, or targeted conventional therapies. However, larger DNA viruses are able to express one or more transgenes; thus, therapeutic mechanisms can be built into the viral vector itself. The incorporated approaches into arming oncolytic viruses through transgene expression will be the main focus of this review, including use of immune activators, prodrug converting enzymes, anti-angiogenic factors, and targeting of the stroma. This will focus on poxviruses as model systems with large cloning capacities, which have routinely been used as transgene expression vectors in different settings, including vaccine and oncolytic viral therapy.Keywords: vaccinia, poxvirus, immunotherapy, angiogenesis, prodrug

  8. Oncolytic adenovirus expressing interferon alpha in a syngeneic Syrian hamster model for the treatment of pancreatic cancer.

    Science.gov (United States)

    LaRocca, Christopher J; Han, Joohee; Gavrikova, Tatyana; Armstrong, Leonard; Oliveira, Amanda R; Shanley, Ryan; Vickers, Selwyn M; Yamamoto, Masato; Davydova, Julia

    2015-05-01

    The addition of interferon (IFN) alpha to adjuvant chemoradiotherapy regimens resulted in remarkable improvements in survival for pancreatic cancer patients. However, systemic toxicities and insufficient levels of IFN at the tumor sites have limited its widespread adoption in treatment schemes. We have previously developed an IFN-expressing conditionally replicative oncolytic adenovirus and demonstrated its therapeutic effects both in vitro and in vivo. Here, the same vectors were tested in a syngeneic and immunocompetent Syrian hamster model to better understand the roles of adenoviral replication and of the pleiotropic effects of IFN on pancreatic tumor growth suppression. Oncolytic adenoviruses expressing human or hamster IFN were designed and generated. Viral vectors were tested in vitro to determine qualitative and quantitative cell viability, cyclooxygenase 2 (Cox2) promoter activity, and IFN production. For the in vivo studies, subcutaneous hamster pancreatic cancer tumors were treated with 1 intratumoral dose of virus. Similarly, 1 intraperitoneal dose of virus was used to prolong survival in a carcinomatosis model. All cell lines tested demonstrated Cox2 promoter activity. The oncolytic potential of a replication competent adenovirus expressing the IFN cytokine was clearly demonstrated. These viruses resulted in significant tumor growth suppression and survival increases compared with controls in a hamster model. The profound therapeutic potential of an IFN-expressing oncolytic adenovirus for the treatment of pancreatic cancer was demonstrated in a syngeneic Syrian hamster model. These results strongly suggest the potential application of our viruses as part of combination regimens with other therapeutics. Published by Elsevier Inc.

  9. Application of interferon modulators to overcome partial resistance of human ovarian cancers to VSV-GP oncolytic viral therapy

    Directory of Open Access Journals (Sweden)

    Catherine Dold

    2016-01-01

    Full Text Available Previously, we described an oncolytic vesicular stomatitis virus variant pseudotyped with the nonneurotropic glycoprotein of the lymphocytic choriomeningitis virus, VSV-GP, which was highly effective in glioblastoma. Here, we tested its potency for the treatment of ovarian cancer, a leading cause of death from gynecological malignancies. Effective oncolytic activity of VSV-GP could be demonstrated in ovarian cancer cell lines and xenografts in mice; however, remission was temporary in most mice. Analysis of the innate immune response revealed that ovarian cancer cell lines were able to respond to and produce type I interferon, inducing an antiviral state upon virus infection. This is in stark contrast to published data for other cancer cell lines, which were mostly found to be interferon incompetent. We showed that in vitro this antiviral state could be reverted by combining VSV-GP with the JAK1/2-inhibitor ruxolitinib. In addition, for the first time, we report the in vivo enhancement of oncolytic virus treatment by ruxolitinib, both in subcutaneous as well as in orthotopic xenograft mouse models, without causing significant additional toxicity. In conclusion, VSV-GP has the potential to be a potent and safe oncolytic virus to treat ovarian cancer, especially when combined with an inhibitor of the interferon response.

  10. Application of interferon modulators to overcome partial resistance of human ovarian cancers to VSV-GP oncolytic viral therapy.

    Science.gov (United States)

    Dold, Catherine; Rodriguez Urbiola, Carles; Wollmann, Guido; Egerer, Lisa; Muik, Alexander; Bellmann, Lydia; Fiegl, Heidelinde; Marth, Christian; Kimpel, Janine; von Laer, Dorothee

    2016-01-01

    Previously, we described an oncolytic vesicular stomatitis virus variant pseudotyped with the nonneurotropic glycoprotein of the lymphocytic choriomeningitis virus, VSV-GP, which was highly effective in glioblastoma. Here, we tested its potency for the treatment of ovarian cancer, a leading cause of death from gynecological malignancies. Effective oncolytic activity of VSV-GP could be demonstrated in ovarian cancer cell lines and xenografts in mice; however, remission was temporary in most mice. Analysis of the innate immune response revealed that ovarian cancer cell lines were able to respond to and produce type I interferon, inducing an antiviral state upon virus infection. This is in stark contrast to published data for other cancer cell lines, which were mostly found to be interferon incompetent. We showed that in vitro this antiviral state could be reverted by combining VSV-GP with the JAK1/2-inhibitor ruxolitinib. In addition, for the first time, we report the in vivo enhancement of oncolytic virus treatment by ruxolitinib, both in subcutaneous as well as in orthotopic xenograft mouse models, without causing significant additional toxicity. In conclusion, VSV-GP has the potential to be a potent and safe oncolytic virus to treat ovarian cancer, especially when combined with an inhibitor of the interferon response.

  11. Establishing the lysine-rich protein CEST reporter gene as a CEST MR imaging detector for oncolytic virotherapy

    NARCIS (Netherlands)

    C.T. Farrar (Christian T.); J.S. Buhrman (Jason); G. Liu (Guanshu); A. Kleijn (Anne); M.L.M. Lamfers (Martine); M.T. McMahon (Michael T.); A.A. Gilad (Assaf A.); G. Fulci (Giulia)

    2015-01-01

    textabstractPurpose: To (a) evaluate whether the lysine-rich protein (LRP) magnetic resonance (MR) imaging reporter gene can be engineered into G47Δ, a herpes simplex-derived oncolytic virus that is currently being tested in clinical trials, without disrupting its therapeutic effectiveness and (b)

  12. Pediatric cancer gone viral. Part II: potential clinical application of oncolytic herpes simplex virus-1 in children

    Directory of Open Access Journals (Sweden)

    Gregory K Friedman

    Full Text Available Oncolytic engineered herpes simplex viruses (HSVs possess many biologic and functional attributes that support their use in clinical trials in children with solid tumors. Tumor cells, in an effort to escape regulatory mechanisms that would impair their growth and progression, have removed many mechanisms that would have protected them from virus infection and eventual virus-mediated destruction. Viruses engineered to exploit this weakness, like mutant HSV, can be safely employed as tumor cell killers, since normal cells retain these antiviral strategies. Many preclinical studies and early phase trials in adults demonstrated that oncolytic HSV can be safely used and are highly effective in killing tumor cells that comprise pediatric malignancies, without generating the toxic side effects of nondiscriminatory chemotherapy or radiation therapy. A variety of engineered viruses have been developed and tested in numerous preclinical models of pediatric cancers and initial trials in patients are underway. In Part II of this review series, we examine the preclinical evidence to support the further advancement of oncolytic HSV in the pediatric population. We discuss clinical advances made to date in this emerging era of oncolytic virotherapy.

  13. The in vivo therapeutic efficacy of the oncolytic adenovirus Delta24-RGD is mediated by tumor-specific immunity

    NARCIS (Netherlands)

    A. Kleijn (Anne); J.J. Kloezeman (Jenneke); E. Treffers-Westerlaken (Elike); G. Fulci (Giulia); S. Leenstra (Sieger); C.M.F. Dirven (Clemens); J.E.M.A. Debets (Reno); M.L.M. Lamfers (Martine)

    2014-01-01

    textabstractThe oncolytic adenovirus Delta24-RGD represents a new promising therapeutic agent for patients with a malignant glioma and is currently under investigation in clinical phase I/II trials. Earlier preclinical studies showed that Delta24-RGD is able to effectively lyse tumor cells, yielding

  14. Permissivity of the NCI-60 cancer cell lines to oncolytic Vaccinia Virus GLV-1h68

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    Bedognetti Davide

    2011-10-01

    Full Text Available Abstract Background Oncolytic viral therapy represents an alternative therapeutic strategy for the treatment of cancer. We previously described GLV-1h68, a modified Vaccinia Virus with exclusive tropism for tumor cells, and we observed a cell line-specific relationship between the ability of GLV-1h68 to replicate in vitro and its ability to colonize and eliminate tumor in vivo. Methods In the current study we surveyed the in vitro permissivity to GLV-1h68 replication of the NCI-60 panel of cell lines. Selected cell lines were also tested for permissivity to another Vaccinia Virus and a vesicular stomatitis virus (VSV strain. In order to identify correlates of permissity to viral infection, we measured transcriptional profiles of the cell lines prior infection. Results We observed highly heterogeneous permissivity to VACV infection amongst the cell lines. The heterogeneity of permissivity was independent of tissue with the exception of B cell derivation. Cell lines were also tested for permissivity to another Vaccinia Virus and a vesicular stomatitis virus (VSV strain and a significant correlation was found suggesting a common permissive phenotype. While no clear transcriptional pattern could be identified as predictor of permissivity to infection, some associations were observed suggesting multifactorial basis permissivity to viral infection. Conclusions Our findings have implications for the design of oncolytic therapies for cancer and offer insights into the nature of permissivity of tumor cells to viral infection.

  15. Oncolytic vesicular stomatitis virus expressing interferon-σ has enhanced therapeutic activity

    Directory of Open Access Journals (Sweden)

    Marie-Claude Bourgeois-Daigneault

    2016-01-01

    Full Text Available Oncolytic viruses are known to stimulate the antitumor immune response by specifically replicating in tumor cells. This is believed to be an important aspect of the durable responses observed in some patients and the field is rapidly moving toward immunotherapy. As a further means to engage the immune system, we engineered a virus, vesicular stomatitis virus (VSV, to encode the proinflammatory cytokine interferon-σ. We used the 4T1 mammary adenocarcinoma as well as other murine tumor models to characterize immune responses in tumor-bearing animals generated by treatment with our viruses. The interferon-σ-encoding virus demonstrated greater activation of dendritic cells and drove a more profound secretion of proinflammatory cytokines compared to the parental virus. From a therapeutic point of view, the interferon-σ virus slowed tumor growth, minimized lung tumors, and prolonged survival in several murine tumor models. The improved efficacy was lost in immunocompromized animals; hence the mechanism appears to be T-cell-mediated. Taken together, these results demonstrate the ability of oncolytic viruses to act as immune stimulators to drive antitumor immunity as well as their potential for targeted gene therapy.

  16. Dimethyl fumarate potentiates oncolytic virotherapy through NF-κB inhibition.

    Science.gov (United States)

    Selman, Mohammed; Ou, Paula; Rousso, Christopher; Bergeron, Anabel; Krishnan, Ramya; Pikor, Larissa; Chen, Andrew; Keller, Brian A; Ilkow, Carolina; Bell, John C; Diallo, Jean-Simon

    2018-01-24

    Resistance to oncolytic virotherapy is frequently associated with failure of tumor cells to get infected by the virus. Dimethyl fumarate (DMF), a common treatment for psoriasis and multiple sclerosis, also has anticancer properties. We show that DMF and various fumaric and maleic acid esters (FMAEs) enhance viral infection of cancer cell lines as well as human tumor biopsies with several oncolytic viruses (OVs), improving therapeutic outcomes in resistant syngeneic and xenograft tumor models. This results in durable responses, even in models otherwise refractory to OV and drug monotherapies. The ability of DMF to enhance viral spread results from its ability to inhibit type I interferon (IFN) production and response, which is associated with its blockade of nuclear translocation of the transcription factor nuclear factor κB (NF-κB). This study demonstrates that unconventional application of U.S. Food and Drug Administration-approved drugs and biological agents can result in improved anticancer therapeutic outcomes. Copyright © 2018 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.

  17. Cancer-targeted oncolytic adenoviruses for modulation of the immune system.

    Science.gov (United States)

    Cerullo, Vincenzo; Capasso, Cristian; Vähä-Koskela, Markus; Hemminki, Otto; Hemminki, Akseli

    2017-05-02

    Adenovirus is one of the most commonly used vectors for gene therapy and it is the first approved virus-derived drug for treatment of cancer. As an oncolytic agent, it can induce lysis of infected cells, but it can also engage the immune system, promoting activation and maturation of antigen-presenting cells (APCs). In essence, oncolysis combined with the associated immunostimulatory actions result in a "personalized in situ vaccine" for each patient. In order to take full advantage of these features, we should try to understand how adenovirus interacts with the immune system, what are the receptors involved in triggering subsequent signals and which kind of responses they elicit. Tackling these questions will give us further insight in how to manipulate adenovirus-mediated immune responses for enhancement of anti-tumor efficacy. In this review, we first highlight how oncolytic adenovirus interacts with the innate immune system and its receptors such as Toll-like receptors, nucleotide-binding and oligomerization domain (NOD)-like receptors and other immune sensors. Then we describe the effect of these interactions on the adaptive immune system and its cells, especially B and T lymphocytes. Finally, we summarize the most significant preclinical and clinical results in the field of gene therapy where researchers have engineered adenovirus to manipulate the host immune system by expressing cytokines and signaling mediators. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  18. Newly Characterized Murine Undifferentiated Sarcoma Models Sensitive to Virotherapy with Oncolytic HSV-1 M002

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    Eric K. Ring

    2017-12-01

    Full Text Available Despite advances in conventional chemotherapy, surgical techniques, and radiation, outcomes for patients with relapsed, refractory, or metastatic soft tissue sarcomas are dismal. Survivors often suffer from lasting morbidity from current treatments. New targeted therapies with less toxicity, such as those that harness the immune system, and immunocompetent murine sarcoma models to test these therapies are greatly needed. We characterized two new serendipitous murine models of undifferentiated sarcoma (SARC-28 and SARC-45 and tested their sensitivity to virotherapy with oncolytic herpes simplex virus 1 (HSV-1. Both models expressed high levels of the primary HSV entry molecule nectin-1 (CD111 and were susceptible to killing by interleukin-12 (IL-12 producing HSV-1 M002 in vitro and in vivo. M002 resulted in a significant intratumoral increase in effector CD4+ and CD8+ T cells and activated monocytes, and a decrease in myeloid-derived suppressor cells (MDSCs in immunocompetent mice. Compared to parent virus R3659 (no IL-12 production, M002 resulted in higher CD8:MDSC and CD8:T regulatory cell (Treg ratios, suggesting that M002 creates a more favorable immune tumor microenvironment. These data provide support for clinical trials targeting sarcomas with oncolytic HSV-1. These models provide an exciting opportunity to explore combination therapies for soft tissue sarcomas that rely on an intact immune system to reach full therapeutic potential.

  19. Activating Peripheral Innate Immunity Enables Safe and Effective Oncolytic Virotherapy in the Brain

    Directory of Open Access Journals (Sweden)

    Lukxmi Balathasan

    2017-12-01

    Full Text Available The oncolytic mutant vesicular stomatitis virus VSVΔ51 achieves robust efficacy in multiple extracranial tumor models. Yet for malignancies of the brain, direct intratumoral infusion of VSVΔ51 causes lethal virus-induced neuropathology. Here, we have developed a novel therapeutic regime that uses peripheral immunization with a single sub-lethal dose of VSVΔ51 to establish an acute anti-viral state that enables the safe intracranial (IC infusion of an otherwise lethal dose of VSVΔ51 within just 6 hr. Although type I interferons alone appeared insufficient to explain this protective phenotype, serum isolated at early time points from primed animals conferred protection against an IC dose of virus. Adaptive immune populations had minimal contributions. Finally, the therapeutic utility of this novel strategy was demonstrated by peripherally priming and intracranially treating mice bearing aggressive CT2A syngeneic astrocytomas with VSVΔ51. Approximately 25% of animals achieved complete regression of established tumors, with no signs of virus-induced neurological impairment. This approach may harness an early warning system in the brain that has evolved to protect the host against otherwise lethal neurotropic viral infections. We have exploited this protective mechanism to safely and efficaciously treat brain tumors with an otherwise neurotoxic virus, potentially widening the available treatment options for oncolytic virotherapy in the brain.

  20. Multifaceted oncolytic virus therapy for glioblastoma in an immunocompetent cancer stem cell model.

    Science.gov (United States)

    Cheema, Tooba A; Wakimoto, Hiroaki; Fecci, Peter E; Ning, Jianfang; Kuroda, Toshihiko; Jeyaretna, Deva S; Martuza, Robert L; Rabkin, Samuel D

    2013-07-16

    Glioblastoma (World Health Organization grade IV) is an aggressive adult brain tumor that is inevitably fatal despite surgery, radiation, and chemotherapy. Treatment failures are attributed to combinations of cellular heterogeneity, including a subpopulation of often-resistant cancer stem cells, aberrant vasculature, and noteworthy immune suppression. Current preclinical models and treatment strategies do not incorporate or address all these features satisfactorily. Herein, we describe a murine glioblastoma stem cell (GSC) model that recapitulates tumor heterogeneity, invasiveness, vascularity, and immunosuppressive microenvironment in syngeneic immunocompetent mice and should prove useful for a range of therapeutic studies. Using this model, we tested a genetically engineered oncolytic herpes simplex virus that is armed with an immunomodulatory cytokine, interleukin 12 (G47-mIL12). G47Δ-mIL12 infects and replicates similarly to its unarmed oncolytic herpes simplex virus counterpart in mouse 005 GSCs in vitro, whereas in vivo, it significantly enhances survival in syngeneic mice bearing intracerebral 005 tumors. Mechanistically, G47-mIL12 targets not only GSCs but also increases IFN-γ release, inhibits angiogenesis, and reduces the number of regulatory T cells in the tumor. The increased efficacy is dependent upon T cells, but not natural killer cells. Taken together, our findings demonstrate that G47Δ-mIL12 provides a multifaceted approach to targeting GSCs, tumor microenvironment, and the immune system, with resultant therapeutic benefit in a stringent glioblastoma model.

  1. Oncolytic virotherapy for malignant glioma: translating laboratory insights into clinical practice

    Directory of Open Access Journals (Sweden)

    Brenda eAuffinger

    2013-02-01

    Full Text Available Glioblastoma multiforme, one of the most common and aggressive brain tumors in adults, is highly resistant to currently available therapies and often recurs. Due to its poor prognosis and difficult management, there is an urgent need for the development and translation of new anti-glioma therapeutic approaches into the clinic. In this context, oncolytic virotherapy arises as an exciting treatment option for glioma patients. These natural or genetically engineered viruses are able to effectively infect cancer cells, inducing a specific anti-tumor cytotoxic effect. In addition, some viruses have been redesigned to specially modulate glioma microenvironment, to express cytokines to boost a systemic anti-glioma immune response and to incorporate angiostatic genes to decrease glioma vasculature. Although recent clinical trials have confirmed the safety of oncolytic virotherapies in the brain, their moderate clinical efficacy has not yet matched the encouraging preclinical laboratory results. In this review, we will discuss the leading anti-glioma virotherapy approaches that are presently under preclinical and clinical evaluation. We will also review different delivery methods, in vivo virus behavior, fate, replication, and intratumoral spread, activation of antitumor immune response and targeting of glioma stem cells. We will focus on the advantages and limitations of each therapeutic approach and how to overcome these hurdles to effectively translate exciting laboratory results into promising clinical trials.

  2. Oncolytic virotherapy for malignant glioma: translating laboratory insights into clinical practice.

    Science.gov (United States)

    Auffinger, Brenda; Ahmed, Atique U; Lesniak, Maciej S

    2013-01-01

    Glioblastoma multiforme, one of the most common and aggressive brain tumors in adults, is highly resistant to currently available therapies and often recurs. Due to its poor prognosis and difficult management, there is an urgent need for the development and translation of new anti-glioma therapeutic approaches into the clinic. In this context, oncolytic virotherapy arises as an exciting treatment option for glioma patients. These natural or genetically engineered viruses are able to effectively infect cancer cells, inducing a specific anti-tumor cytotoxic effect. In addition, some viruses have been redesigned to modulate glioma microenvironment, to express cytokines to boost a systemic anti-glioma immune response and to incorporate angiostatic genes to decrease glioma vasculature. Although recent clinical trials have confirmed the safety of oncolytic virotherapies in the brain, their moderate clinical efficacy has not yet matched the encouraging preclinical laboratory results. In this review, we will discuss the leading anti-glioma virotherapy approaches that are presently under preclinical and clinical evaluation. We will also review different delivery methods, in vivo virus behavior, fate, replication, intratumoral spread, activation of anti-tumor immune response, and targeting of glioma stem cells. We will focus on the advantages and limitations of each therapeutic approach and how to overcome these hurdles to effectively translate exciting laboratory results into promising clinical trials.

  3. Activating Peripheral Innate Immunity Enables Safe and Effective Oncolytic Virotherapy in the Brain.

    Science.gov (United States)

    Balathasan, Lukxmi; Tang, Vera A; Yadollahi, Beta; Brun, Jan; Labelle, Melanie; Lefebvre, Charles; Swift, Stephanie L; Stojdl, David F

    2017-12-15

    The oncolytic mutant vesicular stomatitis virus VSVΔ51 achieves robust efficacy in multiple extracranial tumor models. Yet for malignancies of the brain, direct intratumoral infusion of VSVΔ51 causes lethal virus-induced neuropathology. Here, we have developed a novel therapeutic regime that uses peripheral immunization with a single sub-lethal dose of VSVΔ51 to establish an acute anti-viral state that enables the safe intracranial (IC) infusion of an otherwise lethal dose of VSVΔ51 within just 6 hr. Although type I interferons alone appeared insufficient to explain this protective phenotype, serum isolated at early time points from primed animals conferred protection against an IC dose of virus. Adaptive immune populations had minimal contributions. Finally, the therapeutic utility of this novel strategy was demonstrated by peripherally priming and intracranially treating mice bearing aggressive CT2A syngeneic astrocytomas with VSVΔ51. Approximately 25% of animals achieved complete regression of established tumors, with no signs of virus-induced neurological impairment. This approach may harness an early warning system in the brain that has evolved to protect the host against otherwise lethal neurotropic viral infections. We have exploited this protective mechanism to safely and efficaciously treat brain tumors with an otherwise neurotoxic virus, potentially widening the available treatment options for oncolytic virotherapy in the brain.

  4. Oncolytic Adenoviruses Armed with Tumor Necrosis Factor Alpha and Interleukin-2 Enable Successful Adoptive Cell Therapy

    Directory of Open Access Journals (Sweden)

    Riikka Havunen

    2017-03-01

    Full Text Available Adoptive cell therapy holds much promise in the treatment of cancer but results in solid tumors have been modest. The notable exception is tumor-infiltrating lymphocyte (TIL therapy of melanoma, but this approach only works with high-dose preconditioning chemotherapy and systemic interleukin (IL-2 postconditioning, both of which are associated with toxicities. To improve and broaden the applicability of adoptive cell transfer, we constructed oncolytic adenoviruses coding for human IL-2 (hIL2, tumor necrosis factor alpha (TNF-α, or both. The viruses showed potent antitumor efficacy against human tumors in immunocompromised severe combined immunodeficiency (SCID mice. In immunocompetent Syrian hamsters, we combined the viruses with TIL transfer and were able to cure 100% of the animals. Cured animals were protected against tumor re-challenge, indicating a memory response. Arming with IL-2 and TNF-α increased the frequency of both CD4+ and CD8+ TILs in vivo and augmented splenocyte proliferation ex vivo, suggesting that the cytokines were important for T cell persistence and proliferation. Cytokine expression was limited to tumors and treatment-related signs of systemic toxicity were absent, suggesting safety. To conclude, cytokine-armed oncolytic adenoviruses enhanced adoptive cell therapy by favorable alteration of the tumor microenvironment. A clinical trial is in progress to study the utility of Ad5/3-E2F-d24-hTNFa-IRES-hIL2 (TILT-123 in human patients with cancer.

  5. Systemic therapy with oncolytic myxoma virus cures established residual multiple myeloma in mice.

    Science.gov (United States)

    Bartee, Eric; Bartee, Mee Y; Bogen, Bjarne; Yu, Xue-Zhong

    2016-01-01

    Multiple myeloma is an incurable malignancy of plasma B-cells. Traditional chemotherapeutic regimes often induce initial tumor regression; however, virtually all patients eventually succumb to relapse caused by either reintroduction of disease during autologous transplant or expansion of chemotherapy resistant minimal residual disease. It has been previously demonstrated that an oncolytic virus known as myxoma can completely prevent myeloma relapse caused by reintroduction of malignant cells during autologous transplant. The ability of this virus to treat established residual disease in vivo, however, remained unknown. Here we demonstrate that intravenous administration of myxoma virus into mice bearing disseminated myeloma results in the elimination of 70-90% of malignant cells within 24 hours. This rapid debulking was dependent on direct contact of myxoma virus with residual myeloma and did not occur through destruction of the hematopoietic bone marrow niche. Importantly, systemic myxoma therapy also induced potent antimyeloma CD8(+) T cell responses which localized to the bone marrow and were capable of completely eradicating established myeloma in some animals. These results demonstrate that oncolytic myxoma virus is not only effective at preventing relapse caused by reinfusion of tumor cells during stem cell transplant, but is also potentially curative for patients bearing established minimal residual disease.

  6. Myxoma virus suppresses proliferation of activated T lymphocytes yet permits oncolytic virus transfer to cancer cells.

    Science.gov (United States)

    Villa, Nancy Y; Wasserfall, Clive H; Meacham, Amy M; Wise, Elizabeth; Chan, Winnie; Wingard, John R; McFadden, Grant; Cogle, Christopher R

    2015-06-11

    Allogeneic hematopoietic cell transplant (allo-HCT) can be curative for certain hematologic malignancies, but the risk of graft-versus-host disease (GVHD) is a major limitation for wider application. Ideally, strategies to improve allo-HCT would involve suppression of T lymphocytes that drive GVHD while sparing those that mediate graft-versus-malignancy (GVM). Recently, using a xenograft model, we serendipitously discovered that myxoma virus (MYXV) prevented GVHD while permitting GVM. In this study, we show that MYXV binds to resting, primary human T lymphocytes but will only proceed into active virus infection after the T cells receive activation signals. MYXV-infected T lymphocytes exhibited impaired proliferation after activation with reduced expression of interferon-γ, interleukin-2 (IL-2), and soluble IL-2Rα, but did not affect expression of IL-4 and IL-10. MYXV suppressed T-cell proliferation in 2 patterns (full vs partial) depending on the donor. In terms of GVM, we show that MYXV-infected activated human T lymphocytes effectively deliver live oncolytic virus to human multiple myeloma cells, thus augmenting GVM by transfer of active oncolytic virus to residual cancer cells. Given this dual capacity of reducing GVHD plus increasing the antineoplastic effectiveness of GVM, ex vivo virotherapy with MYXV may be a promising clinical adjunct to allo-HCT regimens. © 2015 by The American Society of Hematology.

  7. Systemic therapy with oncolytic myxoma virus cures established residual multiple myeloma in mice

    Directory of Open Access Journals (Sweden)

    Eric Bartee

    2016-01-01

    Full Text Available Multiple myeloma is an incurable malignancy of plasma B-cells. Traditional chemotherapeutic regimes often induce initial tumor regression; however, virtually all patients eventually succumb to relapse caused by either reintroduction of disease during autologous transplant or expansion of chemotherapy resistant minimal residual disease. It has been previously demonstrated that an oncolytic virus known as myxoma can completely prevent myeloma relapse caused by reintroduction of malignant cells during autologous transplant. The ability of this virus to treat established residual disease in vivo, however, remained unknown. Here we demonstrate that intravenous administration of myxoma virus into mice bearing disseminated myeloma results in the elimination of 70–90% of malignant cells within 24 hours. This rapid debulking was dependent on direct contact of myxoma virus with residual myeloma and did not occur through destruction of the hematopoietic bone marrow niche. Importantly, systemic myxoma therapy also induced potent antimyeloma CD8+ T cell responses which localized to the bone marrow and were capable of completely eradicating established myeloma in some animals. These results demonstrate that oncolytic myxoma virus is not only effective at preventing relapse caused by reinfusion of tumor cells during stem cell transplant, but is also potentially curative for patients bearing established minimal residual disease.

  8. The control of anaplastic thyroid carcinoma cell lines by oncolytic poxviruses.

    Science.gov (United States)

    Mundi, Neil; Um, Sung; Yoo, John; Rizzo, Giananthony; Black, Morgan; Pinto, Nicole; Palma, David A; Fung, Kevin; MacNeil, Danielle; Mymryk, Joe S; Barrett, John W; Nichols, Anthony C

    2014-09-22

    Anaplastic thyroid cancer (ATC) is rare, but its clinical presentation is often dramatic and aggressive and is nearly uniformly fatal. Oncolytic viral therapy is a potential strategy to improve outcomes for patients suffering with this disease. Seven established ATC cell lines were infected with a panel of poxviruses to identify which virus had the most potential as an oncolytic agent. These included myxoma, vaccinia, and tanapox viruses, all modified to express green fluorescence protein (GFP). Viral proliferation was assessed by fluorescence and viral amplification. The effect on cell line growth was assessed by the Presto Blue metabolic assay and a live-dead assay. A replication assay was performed to assess the production of infectious progeny. An additional five ATC cell lines were tested using the assays described above for susceptibility to vaccinia virus. ATC cell lines were differentially susceptible to each virus. Vaccinia virus was superior to myxoma and tanapox viruses for the control of anaplastic thyroid cancer in vitro. Although subsequent investigation using an expanded panel of cell lines revealed differential susceptibility to vaccinia virus, effective control of cell proliferation was still achieved using higher titers. Vaccinia virus was the most potent of the tested poxviruses and was highly effective in controlling proliferation and inducing cell death in ATC cell lines. The efficacy of these viruses offers hope for improving outcomes for patients suffering with ATC. Copyright © 2014 Elsevier B.V. All rights reserved.

  9. Administration and Handling of Talimogene Laherparepvec: An Intralesional Oncolytic Immunotherapy for Melanoma.

    Science.gov (United States)

    Hoffner, Brianna; Iodice, Gail M; Gasal, Eduard

    2016-03-01

    To describe the administration and handling requirements of oncolytic viruses in the context of talimogene laherparepvec (Imlygic™), a first-in-class oncolytic immunotherapy.
. Study procedures employed in clinical trials, in particular the OPTiM study.
. Evaluation of nursing considerations for administration of talimogene laherparepvec.
. Talimogene laherparepvec is administered through a series of intralesional injections into cutaneous, subcutaneous, or nodal tumors (with ultrasound guidance as needed) during an outpatient clinic visit. A single insertion point is recommended; however, multiple insertion points are acceptable if the tumor radius exceeds the needle's radial reach. Talimogene laherparepvec must be evenly distributed throughout the tumor through each insertion site. Talimogene laherparepvec requires storage at -90°C to -70°C and, once thawed, should be administered immediately or stored in its original vial and carton and protected from light in a refrigerator (2°C to 8°C). 
. Because talimogene laherparepvec can be administered in the outpatient setting, nurses will be pivotal for appropriate integration and administration of this unique and effective therapy.

  10. Oncolytic Virotherapy Promotes Intratumoral T Cell Infiltration and Improves Anti-PD-1 Immunotherapy.

    Science.gov (United States)

    Ribas, Antoni; Dummer, Reinhard; Puzanov, Igor; VanderWalde, Ari; Andtbacka, Robert H I; Michielin, Olivier; Olszanski, Anthony J; Malvehy, Josep; Cebon, Jonathan; Fernandez, Eugenio; Kirkwood, John M; Gajewski, Thomas F; Chen, Lisa; Gorski, Kevin S; Anderson, Abraham A; Diede, Scott J; Lassman, Michael E; Gansert, Jennifer; Hodi, F Stephen; Long, Georgina V

    2017-09-07

    Here we report a phase 1b clinical trial testing the impact of oncolytic virotherapy with talimogene laherparepvec on cytotoxic T cell infiltration and therapeutic efficacy of the anti-PD-1 antibody pembrolizumab. Twenty-one patients with advanced melanoma were treated with talimogene laherparepvec followed by combination therapy with pembrolizumab. Therapy was generally well tolerated, with fatigue, fevers, and chills as the most common adverse events. No dose-limiting toxicities occurred. Confirmed objective response rate was 62%, with a complete response rate of 33% per immune-related response criteria. Patients who responded to combination therapy had increased CD8(+) T cells, elevated PD-L1 protein expression, as well as IFN-γ gene expression on several cell subsets in tumors after talimogene laherparepvec treatment. Response to combination therapy did not appear to be associated with baseline CD8(+) T cell infiltration or baseline IFN-γ signature. These findings suggest that oncolytic virotherapy may improve the efficacy of anti-PD-1 therapy by changing the tumor microenvironment. VIDEO ABSTRACT. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. Dominant-negative fibroblast growth factor receptor expression enhances antitumoral potency of oncolytic herpes simplex virus in neural tumors.

    Science.gov (United States)

    Liu, Ta-Chiang; Zhang, Tingguo; Fukuhara, Hiroshi; Kuroda, Toshihiko; Todo, Tomoki; Canron, Xavier; Bikfalvi, Andreas; Martuza, Robert L; Kurtz, Andreas; Rabkin, Samuel D

    2006-11-15

    Oncolytic herpes simplex viruses (HSV) appear to be a promising platform for cancer therapy. However, efficacy as single agents has thus far been unsatisfactory. Fibroblast growth factor (FGF) signaling is important for the growth and migration of endothelial and tumor cells. Here, we examine the strategy of arming oncolytic HSV with a dominant-negative FGF receptor (dnFGFR) that targets the FGF signaling pathway. A mouse Nf1:p53 malignant peripheral nerve sheath tumor (MPNST) cell line expressing dnFGFR was generated by transfection. The effects of dnFGFR expression on cell growth and migration in vitro and tumor formation in vivo were determined. The dnFGFR transgene was then inserted into oncolytic HSV G47Delta using a bacterial artificial chromosome construction system. Antitumoral and antiangiogenic activities of bG47Delta-dnFGFR were examined. MPNST 61E4 cells expressing dnFGFR grew less well than parental control cells. bG47Delta-dnFGFR showed enhanced killing of both tumor (human U87 glioma and F5 malignant meningioma cells and murine MPNST 61E4 and 37-3-18-4 cells) and proliferating endothelial cells (human umbilical vascular endothelial cell and Py-4-1) in vitro compared with the control vector bG47Delta-empty without inhibiting viral replication. In vivo, bG47Delta-dnFGFR was more efficacious than its nonexpressing parent bG47Delta-empty at inhibiting tumor growth and angiogenesis in both human U87 glioma and mouse 37-3-18-4 MPNST tumors in nude mice. By using multiple therapeutic mechanisms, including destruction of both tumor cells and tumor endothelial cells, an oncolytic HSV encoding dnFGFR enhances antitumor efficacy. This strategy can be applied to other oncolytic viruses and for clinical translation.

  12. Pressure surge attenuator

    Science.gov (United States)

    Christie, Alan M.; Snyder, Kurt I.

    1985-01-01

    A pressure surge attenuation system for pipes having a fluted region opposite crushable metal foam. As adapted for nuclear reactor vessels and heads, crushable metal foam is disposed to attenuate pressure surges.

  13. Synergistic effects of oncolytic reovirus and docetaxel chemotherapy in prostate cancer

    Directory of Open Access Journals (Sweden)

    Prestwich Robin

    2011-06-01

    Full Text Available Abstract Background Reovirus type 3 Dearing (T3D has demonstrated oncolytic activity in vitro, in in vivo murine models and in early clinical trials. However the true potential of oncolytic viruses may only be realized fully in combination with other modalities such as chemotherapy, targeted therapy and radiotherapy. In this study, we examine the oncolytic activity of reovirus T3D and chemotherapeutic agents against human prostate cancer cell lines, with particular focus on the highly metastatic cell line PC3 and the chemotherapeutic agent docetaxel. Docetaxel is the standard of care for metastatic prostate cancer and acts by disrupting the normal process of microtubule assembly and disassembly. Reoviruses have been shown to associate with microtubules and may require this association for efficient viral replication. Methods The effects of reovirus and chemotherapy on in vitro cytotoxicity were investigated in PC3 and Du 145 cells and the interactions between agents were assessed by combination index analysis. An Annexin V/propidium iodide fluorescence-activated cell sorting-based assay was used to determine mode of cell death. The effects of reovirus and docetaxel administered as single agent or combination therapy were tested in vivo in a murine model. The effects of docetaxel and reovirus, alone and together, on microtubule stabilisation were investigated by Western blot analysis. Results Variable degrees of synergistic cytotoxicity were observed in PC3 and Du 145 cells exposed to live reovirus and several chemotherapy agents. Combination of reovirus infection with docetaxel exposure led to increased late apoptotic/necrotic cell populations. Reovirus/docetaxel combined therapy led to reduced tumour growth and increased survival in a PC3 tumour bearing mouse model. Microtubule stabilization was enhanced in PC3 cells treated with reovirus/docetaxel combined therapy compared to other reovirus/chemotherapy combinations. Conclusions The co

  14. Combination of Paclitaxel and MG1 oncolytic virus as a successful strategy for breast cancer treatment.

    Science.gov (United States)

    Bourgeois-Daigneault, Marie-Claude; St-Germain, Lauren Elizabeth; Roy, Dominic Guy; Pelin, Adrian; Aitken, Amelia Sadie; Arulanandam, Rozanne; Falls, Theresa; Garcia, Vanessa; Diallo, Jean-Simon; Bell, John Cameron

    2016-08-08

    Breast cancer is the most common malignant disease amongst Western women. The lack of treatment options for patients with chemotherapy-resistant or recurrent cancers is pushing the field toward the rapid development of novel therapies. The use of oncolytic viruses is a promising approach for the treatment of disseminated diseases like breast cancer, with the first candidate recently approved by the Food and Drug Administration for use in patients. In this report, we demonstrate the compatibility of oncolytic virotherapy and chemotherapy using various murine breast cancer models. This one-two punch has been explored in the past by several groups with different viruses and drugs and was shown to be a successful approach. Our strategy is to combine Paclitaxel, one of the most common drugs used to treat patients with breast cancer, and the oncolytic Rhabdovirus Maraba-MG1, a clinical trial candidate in a study currently recruiting patients with late-stage metastatic cancer. We used the EMT6, 4 T1 and E0771 murine breast cancer models to evaluate in vitro and in vivo the effects of co-treatment with MG1 and Paclitaxel. Treatment-induced cytotoxicity was assessed and plaque assays, flow cytometry, microscopy and immunocytochemistry analysis were performed to quantify virus production and transgene expression. Orthotopically implanted tumors were measured during and after treatment to evaluate efficacy and Kaplan-Meier survival curves were generated. Our data demonstrate not only the compatibility of the treatments, but also their synergistic cytopathic activity. With Paclitaxel, EMT6 and 4 T1 tumors demonstrated increased virus production both in vitro and in vivo. Our results also show that Paclitaxel does not impair the safety profile of the virus treatment. Importantly, when combined, MG1 and the drug controlled tumor growth and prolonged survival. The combination of MG1 and Paclitaxel improved efficacy in all of the breast cancer models we tested and thus is a

  15. Oral vaccination with attenuated Salmonella choleraesuis C500 ...

    African Journals Online (AJOL)

    user

    Oral vaccination with attenuated Salmonella choleraesuis C500 expressing recombinant UreB and. CagA antigens protects mice against Helicobacter pylori. J. G. Chen1, A. X. .... incubated for 1 h at 37°C. Serum IgG were detected by peroxidase- .... Molecular characterization of the 128-kDa immunodominant antigen.

  16. Characterization of the Antiglioma Effect of the Oncolytic Adenovirus VCN-01.

    Directory of Open Access Journals (Sweden)

    Beatriz Vera

    Full Text Available Despite the recent advances in the development of antitumor therapies, the prognosis for patients with malignant gliomas remains dismal. Therapy with tumor-selective viruses is emerging as a treatment option for this devastating disease. In this study we characterize the anti-glioma effect of VCN-01, an improved hyaluronidase-armed pRB-pathway-selective oncolytic adenovirus that has proven safe and effective in the treatment of several solid tumors. VCN-01 displayed a significant cytotoxic effect on glioma cells in vitro. In vivo, in two different orthotopic glioma models, a single intra-tumoral administration of VCN-01 increased overall survival significantly and led to long-term survivors free of disease.

  17. To Infection and Beyond: The Multi-Pronged Anti-Cancer Mechanisms of Oncolytic Viruses.

    Science.gov (United States)

    Cassady, Kevin A; Haworth, Kellie B; Jackson, Josh; Markert, James M; Cripe, Timothy P

    2016-02-04

    Over the past 1-2 decades we have witnessed a resurgence of efforts to therapeutically exploit the attributes of lytic viruses to infect and kill tumor cells while sparing normal cells. We now appreciate that the utility of viruses for treating cancer extends far beyond lytic cell death. Viruses are also capable of eliciting humoral and cellular innate and adaptive immune responses that may be directed not only at virus-infected cells but also at uninfected cancer cells. Here we review our current understanding of this bystander effect, and divide the mechanisms into lytic, cytokine, innate cellular, and adaptive phases. Knowing the key pathways and molecular players during virus infection in the context of the cancer microenvironment will be critical to devise strategies to maximize the therapeutic effects of oncolytic viroimmunotherapy.

  18. JX-594, a targeted oncolytic poxvirus for the treatment of cancer.

    Science.gov (United States)

    Merrick, Alison E; Ilett, Elizabeth J; Melcher, Alan A

    2009-12-01

    JX-594 is a replication-competent Wyeth strain vaccinia virus that was genetically modified to inactive the endogenous thymidine kinase gene and to express human GM-CSF and LacZ genes. In development by Jennerex Inc and licensee Green Cross Corp, the modified virus is a novel therapy for treatment-refractive metastatic malignancies from various sites of origin. Targeted oncolytic virotherapy has demonstrated promise in preclinical studies, and more than ten viral species have subsequently entered clinical trials. JX-594 has been modified to augment the intrinsic targeting and oncolytic potential of the vaccinia virus and to enhance antitumor immunity by the expression of the GM-CSF transgene in situ. In vitro and in vivo animal studies have demonstrated the replication specificity of JX-594 for cancer cell lines and tumors, and the restriction of serum human GM-CSF expression to tumor-bearing animals, resulting in significantly reduced tumor burden and an increase in median survival. In phase I trials, JX-594 was well tolerated, with mild systemic toxicity reported. In a phase I trial in seven patients with melanoma, one partial response and one complete response after surgery were observed. In another phase I trial in patients with hepatic carcinoma, three out of ten evaluable patients had a partial response and six had stable disease; the MTD was also established. A phase II trial in patients (expected n = 30) with unresectable primary hepatocellular carcinoma was recruiting at the time of publication, with completion expected in March 2010, and a phase III trial in patients with hepatocellular carcinoma was planned for the second half of 2010. Further clinical investigations are needed to explore the potential of this agent as a single therapy and as part of multimodal treatment regimens.

  19. Tunneling nanotubes: an alternate route for propagation of the bystander effect following oncolytic viral infection

    Directory of Open Access Journals (Sweden)

    Justin Ady

    2016-01-01

    Full Text Available Tunneling nanotubes (TNTs are ultrafine, filamentous actin-based cytoplasmic extensions which form spontaneously to connect cells at short and long-range distances. We have previously described long-range intercellular communication via TNTs connecting mesothelioma cells in vitro and demonstrated TNTs in intact tumors from patients with mesothelioma. Here, we investigate the ability of TNTs to mediate a viral thymidine kinase based bystander effect after oncolytic viral infection and administration of the nucleoside analog ganciclovir. Using confocal microscopy we assessed the ability of TNTs to propagate enhanced green fluorescent protein (eGFP, which is encoded by the herpes simplex virus NV1066, from infected to uninfected recipient cells. Using time-lapse imaging, we observed eGFP expressed in infected cells being transferred via TNTs to noninfected cells; additionally, increasing fluorescent activity in recipient cells indicated cell-to-cell transmission of the eGFP-expressing NV1066 virus had also occurred. TNTs mediated cell death as a form of direct cell-to-cell transfer following viral thymidine kinase mediated activation of ganciclovir, inducing a unique long-range form of the bystander effect through transmission of activated ganciclovir to nonvirus-infected cells. Thus, we provide proof-of-principle demonstration of a previously unknown and alternative mechanism for inducing apoptosis in noninfected recipient cells. The conceptual advance of this work is that TNTs can be harnessed for delivery of oncolytic viruses and of viral thymidine kinase activated drugs to amplify the bystander effect between cancer cells over long distances in stroma-rich tumor microenvironments.

  20. Treatment strategies for combining immunostimulatory oncolytic virus therapeutics with dendritic cell injections.

    Science.gov (United States)

    Wares, Joanna R; Crivelli, Joseph J; Yun, Chae-Ok; Choi, Il-Kyu; Gevertz, Jana L; Kim, Peter S

    2015-12-01

    Oncolytic viruses (OVs) are used to treat cancer, as they selectively replicate inside of and lyse tumor cells. The efficacy of this process is limited and new OVs are being designed to mediate tumor cell release of cytokines and co-stimulatory molecules, which attract cytotoxic T cells to target tumor cells, thus increasing the tumor-killing effects of OVs. To further promote treatment efficacy, OVs can be combined with other treatments, such as was done by Huang et al., who showed that combining OV injections with dendritic cell (DC) injections was a more effective treatment than either treatment alone. To further investigate this combination, we built a mathematical model consisting of a system of ordinary differential equations and fit the model to the hierarchical data provided from Huang et al. We used the model to determine the effect of varying doses of OV and DC injections and to test alternative treatment strategies. We found that the DC dose given in Huang et al. was near a bifurcation point and that a slightly larger dose could cause complete eradication of the tumor. Further, the model results suggest that it is more effective to treat a tumor with immunostimulatory oncolytic viruses first and then follow-up with a sequence of DCs than to alternate OV and DC injections. This protocol, which was not considered in the experiments of Huang et al., allows the infection to initially thrive before the immune response is enhanced. Taken together, our work shows how the ordering, temporal spacing, and dosage of OV and DC can be chosen to maximize efficacy and to potentially eliminate tumors altogether.

  1. pH-sensitive oncolytic adenovirus hybrid targeting acidic tumor microenvironment and angiogenesis.

    Science.gov (United States)

    Choi, Joung-Woo; Jung, Soo-Jung; Kasala, Dayananda; Hwang, June Kyu; Hu, Jun; Bae, You Han; Yun, Chae-Ok

    2015-05-10

    Although oncolytic adenoviruses (Ads) are an attractive option for cancer gene therapy, the intravenous administration of naked Ad still encounters unfavorable host responses, non-specific interactions, and heterogeneity in targeted cancer cells. To overcome these obstacles and achieve specific targeting of the tumor microenvironment, Ad was coated with the pH-sensitive block copolymer, methoxy poly(ethylene glycol)-b-poly(l-histidine-co-l-phenylalanine) (PEGbPHF). The physicochemical properties of the generated nanocomplex, Ad/PEGbPHF, were assessed. At pH6.4, GFP-expressing Ad/PEGbPHF induced significantly higher GFP expression than naked Ad in both coxsackie and adenovirus receptor (CAR)-positive and -negative cells. To assess the therapeutic efficacy of the Ad/PEGbPHF complex platform, an oncolytic Ad expressing VEGF promoter-targeting transcriptional repressor (KOX) was used to form complexes. At pH6.4, KOX/PEGbPHF significantly suppressed VEGF gene expression, cancer cell migration, vessel sprouting, and cancer cell killing effect compared to naked KOX or KOX/PEGbPHF at pH7.4, demonstrating that KOX/PEGbPHF can overcome the lack of CAR that is frequently observed in tumor tissues. The antitumor activity of KOX/PEGbPHF systemically administered to a tumor xenograft model was significantly higher than that of naked KOX. Furthermore, KOX/PEGbPHF showed lower hepatic toxicity and did not induce an innate immune response against Ad. Altogether, these results demonstrate that pH-sensitive polymer-coated Ad complex significantly increases net positive charge upon exposure to hypoxic tumor microenvironment, allowing passive targeting to the tumor tissue. It may offer superior potential for systemic therapy, due to its improved tumor selectivity, increased therapeutic efficacy, and lower toxicity compared to naked KOX. Copyright © 2015 Elsevier B.V. All rights reserved.

  2. p21 promotes oncolytic adenoviral activity in ovarian cancer and is a potential biomarker

    Directory of Open Access Journals (Sweden)

    Lockley Michelle

    2010-07-01

    Full Text Available Abstract The oncolytic adenovirus dl922-947 replicates selectively within and lyses cells with a dysregulated Rb pathway, a finding seen in > 90% human cancers. dl922-947 is more potent than wild type adenovirus and the E1B-deletion mutant dl1520 (Onyx-015. We wished to determine which host cell factors influence cytotoxicity. SV40 large T-transformed MRC5-VA cells are 3-logs more sensitive to dl922-947 than isogenic parental MRC5 cells, confirming that an abnormal G1/S checkpoint increases viral efficacy. The sensitivity of ovarian cancer cells to dl922-947 varied widely: IC50 values ranged from 51 (SKOV3ip1 to 0.03 pfu/cell (TOV21G. Cells sensitive to dl922-947 had higher S phase populations and supported earlier E1A expression. Cytotoxicity correlated poorly with both infectivity and replication, but well with expression of p21 by microarray and western blot analyses. Matched p21+/+ and -/- Hct116 cells confirmed that p21 influences dl922-947 activity in vitro and in vivo. siRNA-mediated p21 knockdown in sensitive TOV21G cells decreases E1A expression and viral cytotoxicity, whilst expression of p21 in resistant A2780CP cells increases virus activity in vitro and in intraperitoneal xenografts. These results highlight that host cell factors beyond simple infectivity can influence the efficacy of oncolytic adenoviruses. p21 expression may be an important biomarker of response in clinical trials.

  3. Hepatoma targeting peptide conjugated bio-reducible polymer complexed with oncolytic adenovirus for cancer gene therapy.

    Science.gov (United States)

    Choi, Joung-Woo; Kim, Hyun Ah; Nam, Kihoon; Na, Youjin; Yun, Chae-Ok; Kim, SungWan

    2015-12-28

    Despite adenovirus (Ad) vector's numerous advantages for cancer gene therapy, such as high ability of endosomal escape, efficient nuclear entry mechanism, and high transduction, and therapeutic efficacy, tumor specific targeting and antiviral immune response still remain as a critical challenge in clinical setting. To overcome these obstacles and achieve cancer-specific targeting, we constructed tumor targeting bioreducible polymer, an arginine grafted bio-reducible polymer (ABP)-PEG-HCBP1, by conjugating PEGylated ABP with HCBP1 peptides which has high affinity and selectivity towards hepatoma. The ABP-PEG-HCBP1-conjugated replication incompetent GFP-expressing ad, (Ad/GFP)-ABP-PEG-HCBP1, showed a hepatoma cancer specific uptake and transduction compared to either naked Ad/GFP or Ad/GFP-ABP. Competition assays demonstrated that Ad/GFP-ABP-PEG-HCBP1-mediated transduction was specifically inhibited by HCBP1 peptide rather than coxsackie and adenovirus receptor specific antibody. In addition, ABP-PEG-HCBP1 can protect biological activity of Ad against serum, and considerably reduced both innate and adaptive immune response against Ad. shMet-expressing oncolytic Ad (oAd; RdB/shMet) complexed with ABP-PEG-HCBP1 delivered oAd efficiently into hepatoma cancer cells. The oAd/ABP-PEG-HCBP1 demonstrated enhanced cancer cell killing efficacy in comparison to oAd/ABP complex. Furthermore, Huh7 and HT1080 cancer cells treated with oAd/shMet-ABP-PEG-HCBP1 complex had significantly decreased Met and VEGF expression in hepatoma cancer, but not in non-hepatoma cancer. In sum, these results suggest that HCBP1-conjugated bioreducible polymer could be used to deliver oncolytic Ad safely and efficiently to treat hepatoma. Copyright © 2015 Elsevier B.V. All rights reserved.

  4. STAT3 inhibition reduces toxicity of oncolytic VSV and provides a potentially synergistic combination therapy for hepatocellular carcinoma.

    Science.gov (United States)

    Marozin, S; Altomonte, J; Muñoz-Álvarez, K A; Rizzani, A; De Toni, E N; Thasler, W E; Schmid, R M; Ebert, O

    2015-06-01

    Hepatocellular carcinoma (HCC) is a refractory malignancy with a high mortality and increasing worldwide incidence rates, including the United States and central Europe. In this study, we demonstrate that a specific inhibitor of signal transducer and activator of transcription 3 (STAT3), NSC74859, efficiently reduces HCC cell proliferation and can be successfully combined with oncolytic virotherapy using vesicular stomatitis virus (VSV). The potential benefits of this combination treatment are strengthened by the ability of NSC74859 to protect primary hepatocytes and nervous system cells against virus-induced cytotoxicity, with an elevation of the VSV maximum tolerated dose in mice. Hereby we propose a strategy for improving the current regimen for HCC treatment and seek to further explore the molecular mechanisms underlying selective oncolytic specificity of VSV.

  5. Endothelial progenitor cells as cellular vehicles to deliver oncolytic virus therapies to metastatic tumors: the "Trojan horse" approach.

    Science.gov (United States)

    Deng, Wei; Jia, Jun

    2008-01-01

    In view of the limited success of available treatment modalities for metastatic tumor, alternative and complementary strategies need to be developed. Oncolytic viruses are capable of selective replication in malignant cells and therefore offer levels of potency and specificity that are potentially far higher than conventional treatments for tumor. However, lack of systemic delivery technique for therapeutic viruses impacts their application in treating patients with multiple disseminated metastases. Recent studies have demonstrated that when being transplanted, endothelial progenitor cells can migrate via peripheral blood and home exclusively to the site of tumor neovasculature. We hypothesized that endothelial progenitor cells can act as "Trojan horse" to systemically deliver oncolytic virus to metastases in order to inhibit tumor neovascularization formation and eventually eradicate the metastatic tumor.

  6. Discovery of a 9-mer Cationic Peptide (LTX-315) as a Potential First in Class Oncolytic Peptide.

    Science.gov (United States)

    Haug, Bengt Erik; Camilio, Ketil André; Eliassen, Liv Tone; Stensen, Wenche; Svendsen, John Sigurd; Berg, Kristel; Mortensen, Bjarte; Serin, Guillaume; Mirjolet, Jean-Francois; Bichat, Francis; Rekdal, Øystein

    2016-04-14

    Oncolytic immunotherapies represent a new promising strategy in the treatment of cancer. In our efforts to develop oncolytic peptides, we identified a series of chemically modified 9-mer cationic peptides that were highly effective against both drug-resistant and drug-sensitive cancer cells and with lower toxicity toward normal cells. Among these peptides, LTX-315 displayed superior anticancer activity and was selected as a lead candidate. This peptide showed relative high plasma protein binding abilities and a human plasma half-life of 160 min, resulting in formation of nontoxic metabolites. In addition, the lead candidate demonstrated relatively low ability to inhibit CYP450 enzymes. Collectively these data indicated that this peptide has potential to be developed as a new anticancer agent for intratumoral administration and is currently being evaluated in a phase I/IIa study.

  7. Oncolytic potency of HER-2 retargeted VSV-FH hybrid viruses: the role of receptor ligand affinity.

    Science.gov (United States)

    Ayala Breton, Camilo; Wikan, Nitwara; Abbuhl, Arinda; Smith, Duncan R; Russell, Stephen J; Peng, Kah-Whye

    2015-01-01

    The hybrid oncolytic vesicular stomatitis virus (VSV-FH) deleted for its G glycoprotein and displaying the measles virus (MV) envelope glycoproteins (hemagglutinin H and fusion F) is fusogenic, infects cells via any of the three MV receptors and has potent oncolytic activity against subcutaneous and disseminated myeloma tumors. To tailor VSV-FH as an oncolytic virus for ovarian cancer, we ablated its natural tropism and retargeted the virus by display of a single-chain antibody (scFv) with specificity to the HER-2/neu receptor. A panel of six VSVFH-αHER2 viruses displaying anti-HER2 scFv that bind to the same HER2 epitope but with different K d (10(-6) to 10(-11) M, VSVFH-αHER2#6 to #11, respectively) were rescued and characterized. A K d of at least 10(-8) M is required for infection of HER-2 positive SKOV3ip.1 cells. The higher affinity viruses (>10(-8) M) were able to infect and fuse SKOV3ip.1 cells more efficiently, inducing more extensive cytopathic effects. We next compared the antitumor potency of the viruses against SKOV3ip.1 tumor xenografts. In contrast to the saline-treated animals, one intratumoral injection of VSVFH-αHER2#9, #10, or #11 resulted in efficient tumor control. There was no significant difference between viruses with an affinity higher than 10(-9) M in terms of oncolytic potency. VSVFH-αHER2 virus may be a promising agent for the treatment of HER-2 positive malignancies.

  8. Myeloid-derived suppressor cells as a Trojan horse: A cellular vehicle for the delivery of oncolytic viruses.

    Science.gov (United States)

    Pan, Ping-Ying; Chen, Hui-Ming; Chen, Shu-Hsia

    2013-08-01

    We have recently demonstrated that oncolytic vesicular stomatitis viruses can be efficiently and selectively delivered to neoplastic lesions by myeloid-derived suppressor cells (MDSCs). Importantly, the loading of viruses onto MDSCs inhibited their immunosuppressive properties and endowed them with immunostimulatory and tumoricidal functions. Our study demonstrates the potential use of MDSCs as a Trojan horse for the tumor-targeted delivery of various anticancer therapeutics.

  9. Imaging of intratumoral inflammation during oncolytic virotherapy of tumors by 19F-magnetic resonance imaging (MRI.

    Directory of Open Access Journals (Sweden)

    Stephanie Weibel

    Full Text Available BACKGROUND: Oncolytic virotherapy of tumors is an up-coming, promising therapeutic modality of cancer therapy. Unfortunately, non-invasive techniques to evaluate the inflammatory host response to treatment are rare. Here, we evaluate (19F magnetic resonance imaging (MRI which enables the non-invasive visualization of inflammatory processes in pathological conditions by the use of perfluorocarbon nanoemulsions (PFC for monitoring of oncolytic virotherapy. METHODOLOGY/PRINCIPAL FINDINGS: The Vaccinia virus strain GLV-1h68 was used as an oncolytic agent for the treatment of different tumor models. Systemic application of PFC emulsions followed by (1H/(19F MRI of mock-infected and GLV-1h68-infected tumor-bearing mice revealed a significant accumulation of the (19F signal in the tumor rim of virus-treated mice. Histological examination of tumors confirmed a similar spatial distribution of the (19F signal hot spots and CD68(+-macrophages. Thereby, the CD68(+-macrophages encapsulate the GFP-positive viral infection foci. In multiple tumor models, we specifically visualized early inflammatory cell recruitment in Vaccinia virus colonized tumors. Furthermore, we documented that the (19F signal correlated with the extent of viral spreading within tumors. CONCLUSIONS/SIGNIFICANCE: These results suggest (19F MRI as a non-invasive methodology to document the tumor-associated host immune response as well as the extent of intratumoral viral replication. Thus, (19F MRI represents a new platform to non-invasively investigate the role of the host immune response for therapeutic outcome of oncolytic virotherapy and individual patient response.

  10. Myxoma Virus Sensitizes Cancer Cells to Gemcitabine and Is an Effective Oncolytic Virotherapeutic in Models of Disseminated Pancreatic Cancer

    OpenAIRE

    Wennier, Sonia Tusell; Liu, Jia; Li, Shoudong; Rahman, Masmudur M.; Mona, Mahmoud; McFadden, Grant

    2012-01-01

    Myxoma virus (MYXV) is a novel oncolytic virus that has been shown to replicate in pancreatic cancer cells, but its efficacy in animal models of pancreatic cancer has not been determined. The efficacy of MYXV as monotherapy or in combination with gemcitabine was evaluated in intraperitoneal dissemination (IPD) models of pancreatic cancer. The effects of an intact immune system on the efficacy of MYXV therapy was tested by comparing immunodeficient versus immunocompetent murine models and comb...

  11. Selective purging of human multiple myeloma cells from autologous stem cell transplant grafts using oncolytic myxoma virus

    OpenAIRE

    Bartee, Eric; Chan, Winnie S.; Moreb, Jan S.; Cogle, Christopher R.; McFadden, Grant

    2012-01-01

    Autologous stem cell transplantation (ASCT) and novel therapies have improved overall survival of patients with multiple myeloma; however, most patients relapse and eventually succumb to their disease. Evidence indicates that residual cancer cells contaminate autologous grafts and may contribute to early relapses after ASCT. Here, we demonstrate that ex vivo treatment with an oncolytic poxvirus called myxoma virus results in specific elimination of human myeloma cells by inducing rapid cellul...

  12. RGD-modifided oncolytic adenovirus exhibited potent cytotoxic effect on CAR-negative bladder cancer-initiating cells

    OpenAIRE

    Xu, H; Shen, J.; Yang, Y.; Wu, S.; Xiao, J.; Xu, Y.; Liu, X-Y; Chu, L

    2015-01-01

    Cancer-initiating cell (CIC) is critical in cancer development, maintenance and recurrence. The reverse expression pattern of coxsackie and adenovirus receptor (CAR) and ? ? integrin in bladder cancer decreases the infection efficiency of adenovirus. We constructed Arg-Gly-Asp (RGD)-modified oncolytic adenovirus, carrying EGFP or TNF-related apoptosis-inducing ligand (TRAIL) gene (OncoAd.RGD-hTERT-EGFP/TRAIL), and applied them to CAR-negative bladder cancer T24 cells and cancer-initiating T24...

  13. Expression of Recombinant Antibodies

    OpenAIRE

    André eFrenzel; Michael eHust; Thomas eSchirrmann

    2013-01-01

    Recombinant antibodies are highly specific detection probes in research, diagnostics, and have emerged over the last two decades as the fastest growing class of therapeutic proteins. Antibody generation has been dramatically accelerated by in vitro selection systems, particularly phage display. An increasing variety of recombinant production systems have been developed, ranging from Gram-negative and positive bacteria, yeasts and filamentous fungi, insect cell lines, mammalian cells to transg...

  14. Oncolytic Vesicular Stomatitis Virus as a Viro-Immunotherapy: Defeating Cancer with a “Hammer” and “Anvil”

    Directory of Open Access Journals (Sweden)

    Michael Karl Melzer

    2017-02-01

    Full Text Available Oncolytic viruses have gained much attention in recent years, due, not only to their ability to selectively replicate in and lyse tumor cells, but to their potential to stimulate antitumor immune responses directed against the tumor. Vesicular stomatitis virus (VSV, a negative-strand RNA virus, is under intense development as an oncolytic virus due to a variety of favorable properties, including its rapid replication kinetics, inherent tumor specificity, and its potential to elicit a broad range of immunomodulatory responses to break immune tolerance in the tumor microenvironment. Based on this powerful platform, a multitude of strategies have been applied to further improve the immune-stimulating potential of VSV and synergize these responses with the direct oncolytic effect. These strategies include: 1. modification of endogenous virus genes to stimulate interferon induction; 2. virus-mediated expression of cytokines or immune-stimulatory molecules to enhance anti-tumor immune responses; 3. vaccination approaches to stimulate adaptive immune responses against a tumor antigen; 4. combination with adoptive immune cell therapy for potentially synergistic therapeutic responses. A summary of these approaches will be presented in this review.

  15. Enhanced lysis by bispecific oncolytic measles viruses simultaneously using HER2/neu or EpCAM as target receptors

    Directory of Open Access Journals (Sweden)

    Jan RH Hanauer

    2016-01-01

    Full Text Available To target oncolytic measles viruses (MV to tumors, we exploit the binding specificity of designed ankyrin repeat proteins (DARPins. These DARPin-MVs have high tumor selectivity while maintaining excellent oncolytic potency. Stability, small size, and efficacy of DARPins allowed the generation of MVs simultaneously targeted to tumor marker HER2/neu and cancer stem cell (CSC marker EpCAM. For optimization, the linker connecting both DARPins was varied in flexibility and length. Flexibility had no impact on fusion helper activity whereas length had. MVs with bispecific MV-H are genetically stable and revealed the desired double-target specificity. In vitro, the cytolytic activity of bispecific MVs was superior or comparable to mono-targeted viruses depending on the target cells. In vivo, therapeutic efficacy of the bispecific viruses was validated in an orthotopic ovarian carcinoma model revealing an effective reduction of tumor mass. Finally, the power of bispecific targeting was demonstrated on cocultures of different tumor cells thereby mimicking tumor heterogeneity in vitro, more closely reflecting real tumors. Here, bispecific excelled monospecific viruses in efficacy. DARPin-based targeting domains thus allow the generation of efficacious oncolytic viruses with double specificity, with the potential to handle intratumoral variation of antigen expression and to simultaneously target CSCs and the bulk tumor mass.

  16. Viral warfare! Front-line defence and arming the immune system against cancer using oncolytic vaccinia and other viruses.

    Science.gov (United States)

    Dave, R V; Jebar, A H S; Jennings, V A; Adair, R A; West, E J; Errington-Mais, F; Toogood, G J; Melcher, A A

    2014-08-01

    Despite mankind's many achievements, we are yet to find a cure for cancer. We are now approaching a new era which recognises the promise of harnessing the immune system for anti-cancer therapy. Pathogens have been implicated for decades as potential anti-cancer agents, but implementation into clinical therapy has been plagued with significant drawbacks. Newer 'designer' agents have addressed some of these concerns, in particular, a new breed of oncolytic virus: JX-594, a genetically engineered pox virus, is showing promise. To review the current literature on the use of oncolytic viruses in the treatment of cancer; both by direct oncolysis and stimulation of the immune system. The review will provide a background and historical progression for the surgeon on tumour immunology, and the interplay between oncolytic viruses, immune cells, inflammation on tumourigenesis. A literature review was performed using the Medline database. Viral therapeutics hold promise as a novel treatment modality for the treatment of disseminated malignancy. It provides a multi-pronged attack against tumour burden; direct tumour cell lysis, exposure of tumour-associated antigens (TAA), induction of immune danger signals, and recognition by immune effector cells. Copyright © 2014 Royal College of Surgeons of Edinburgh (Scottish charity number SC005317) and Royal College of Surgeons in Ireland. Published by Elsevier Ltd. All rights reserved.

  17. Oncolytic adenoviruses armed with thymidine kinase can be traced by PET imaging and show potent antitumoural effects by ganciclovir dosing.

    Directory of Open Access Journals (Sweden)

    Daniel Abate-Daga

    Full Text Available Replication-competent adenoviruses armed with thymidine kinase (TK combine the concepts of virotherapy and suicide gene therapy. Moreover TK-activity can be detected by noninvasive positron emission-computed tomography (PET imaging, what could potentially facilitate virus monitoring in vivo. Here, we report the generation of a novel oncolytic adenovirus that incorporates the Tat8-TK gene under the control of the Major Late Promoter in a highly selective backbone thus providing selectivity by targeting the retinoblastoma pathway. The selective oncolytic TK virus, termed ICOVIR5-TK-L, showed reduced potency compared to a non-selective counterpart. However the combination of ICOVIR5-TK-L with ganciclovir (GCV induced a potent antitumoural effect similar to that of wild type adenovirus in a preclinical model of pancreatic cancer. Although the treatment with GCV provoked a reduction in the viral yield, both in vitro and in vivo, a two-cycle treatment of virus and GCV resulted in an enhanced antitumoral response that correlated with high TK-activity, based on microPET measurements. Thus, TK-expressing oncolytic adenoviruses can be traced by PET imaging providing real time information on the activity of the virus and its antitumoral potency can be optimized by GCV dosing.

  18. The viral tropism of two distinct oncolytic viruses, reovirus and myxoma virus, is modulated by cellular tumor suppressor gene status.

    Science.gov (United States)

    Kim, M; Williamson, C T; Prudhomme, J; Bebb, D G; Riabowol, K; Lee, P W K; Lees-Miller, S P; Mori, Y; Rahman, M M; McFadden, G; Johnston, R N

    2010-07-08

    Replication-competent oncolytic viruses hold great potential for the clinical treatment of many cancers. Importantly, many oncolytic virus candidates, such as reovirus and myxoma virus, preferentially infect cancer cells bearing abnormal cellular signaling pathways. Reovirus and myxoma virus are highly responsive to activated Ras and Akt signaling pathways, respectively, for their specificity for viral oncolysis. However, considering the complexity of cancer cell populations, it is possible that other tumor-specific signaling pathways may also contribute to viral discrimination between normal versus cancer cells. Because carcinogenesis is a multistep process involving the accumulation of both oncogene activations and the inactivation of tumor suppressor genes, we speculated that not only oncogenes but also tumor suppressor genes may have an important role in determining the tropism of these viruses for cancer cells. It has been previously shown that many cellular tumor suppressor genes, such as p53, ATM and Rb, are important for maintaining genomic stability; dysfunction of these tumor suppressors may disrupt intact cellular antiviral activity due to the accumulation of genomic instability or due to interference with apoptotic signaling. Therefore, we speculated that cells with dysfunctional tumor suppressors may display enhanced susceptibility to challenge with these oncolytic viruses, as previously seen with adenovirus. We report here that both reovirus and myxoma virus preferentially infect cancer cells bearing dysfunctional or deleted p53, ATM and Rb tumor suppressor genes compared to cells retaining normal counterparts of these genes. Thus, oncolysis by these viruses may be influenced by both oncogenic activation and tumor suppressor status.

  19. Retargeted oncolytic adenovirus displaying a single variable domain of camelid heavy-chain-only antibody in a fiber protein

    Directory of Open Access Journals (Sweden)

    Elisabeth A van Erp

    2015-01-01

    Full Text Available Conditionally replicative adenoviruses are promising agents for oncolytic virotherapy. Various approaches have been attempted to retarget adenoviruses to tumor-specific antigens to circumvent deficiency of receptor for adenoviral binding and to provide an additional level of tumor specificity. Functional incorporation of highly specific targeting molecules into the viral capsid can potentially retarget adenoviral infection. However, conventional antibodies are not compatible with the cytoplasmic adenovirus capsid synthesis. The goal of this study was to evaluate the utility of single variable domains derived from heavy chain camelid antibodies for retargeting of adenovirus infection. We have combined transcriptional targeting using a tumor-specific promoter with transductional targeting through viral capsid incorporation of antihuman carcinoembryonic antigen single variable domains. Obtained data demonstrated that employment of a single variable domain genetically incorporated into an adenovirus fiber increased specificity of infection and efficacy of replication of single variable domain-targeted oncolytic adenovirus. The double targeting, both transcriptional through the C-X-C chemokine receptor type 4 promoter and transductional using the single variable domain, is a promising means to improve the therapeutic index for these advanced generation conditionally replicative adenoviruses. A successful strategy to transductional retargeting of oncolytic adenovirus infection has not been shown before and therefore we believe this is the first employment of transductional targeting using single variable domains derived from heavy chain camelid antibodies to enhance specificity of conditionally replicative adenoviruses.

  20. Enhanced Oncolytic Activities of the Telomerase-Specific Replication-Competent Adenovirus Expressing Short-Hairpin RNA against Dicer.

    Science.gov (United States)

    Machitani, Mitsuhiro; Sakurai, Fuminori; Wakabayashi, Keisaku; Tachibana, Masashi; Fujiwara, Toshiyoshi; Mizuguchi, Hiroyuki

    2017-01-01

    Oncolytic viruses have been receiving much attention as potential agents for cancer treatment. Among the various types of oncolytic viruses, the telomerase-specific replication-competent adenovirus (TRAD), which carries the tumor-specific promoter-driven E1 gene expression cassette, exhibits efficient antitumor effects. The development of a novel TRAD that shows higher replication efficiency and antitumor activity would be highly beneficial for safer and more efficient cancer therapy. We recently demonstrated that the endoribonuclease Dicer significantly inhibits the replication of wild-type adenovirus (Ad) via the processing of viral-associated (VA)-RNAs, which are Ad-encoded small noncoding RNAs, and that the knockdown of Dicer leads to enhanced VA-RNA expression and Ad replication after infection with wild-type Ad. Based on these findings, we herein developed a novel TRAD expressing short-hairpin RNA against Dicer (shDicer; TRAD-shDicer). After infection, TRAD-shDicer efficiently induced the knockdown of Dicer. TRAD-shDicer showed significantly higher replication efficiency and tumor cell lysis activity compared with the conventional TRAD in tumor cells. The Dicer expression levels and viabilities of normal cells were not altered by infection with TRAD-shDicer. These results indicate that TRAD-shDicer is a potent antitumor reagent by virtue of its enhanced oncolytic activity. Mol Cancer Ther; 16(1); 251-9. ©2016 AACR. ©2016 American Association for Cancer Research.

  1. Recombinant vaccines against bluetongue virus.

    Science.gov (United States)

    Calvo-Pinilla, Eva; Castillo-Olivares, Javier; Jabbar, Tamara; Ortego, Javier; de la Poza, Francisco; Marín-López, Alejandro

    2014-03-01

    Bluetongue (BT) is a hemorrhagic disease of ruminants caused by bluetongue virus (BTV), the prototype member of the genus Orbivirus within the family Reoviridae and is transmitted via biting midges of the genus Culicoides. BTV can be found on all continents except Antarctica, and up to 26 immunologically distinct BTV serotypes have been identified. Live attenuated and inactivated BTV vaccines have been used over the years with different degrees of success. The multiple outbreaks of BTV in Mediterranean Europe in the last two decades and the incursion of BTV-8 in Northern Europe in 2008 has re-stimulated the interest to develop improved vaccination strategies against BTV. In particular, safer, cross-reactive, more efficacious vaccines with differential diagnostic capability have been pursued by multiple BTV research groups and vaccine manufacturers. A wide variety of recombinant BTV vaccine prototypes have been investigated, ranging from baculovirus-expressed sub-unit vaccines to the use of live viral vectors. This article gives a brief overview of all these modern approaches to develop vaccines against BTV including some recent unpublished data. Copyright © 2013 The Authors. Published by Elsevier B.V. All rights reserved.

  2. Regulation of Meiotic Recombination

    Energy Technology Data Exchange (ETDEWEB)

    Gregory p. Copenhaver

    2011-11-09

    Meiotic recombination results in the heritable rearrangement of DNA, primarily through reciprocal exchange between homologous chromosome or gene conversion. In plants these events are critical for ensuring proper chromosome segregation, facilitating DNA repair and providing a basis for genetic diversity. Understanding this fundamental biological mechanism will directly facilitate trait mapping, conventional plant breeding, and development of genetic engineering techniques that will help support the responsible production and conversion of renewable resources for fuels, chemicals, and the conservation of energy (1-3). Substantial progress has been made in understanding the basal recombination machinery, much of which is conserved in organisms as diverse as yeast, plants and mammals (4, 5). Significantly less is known about the factors that regulate how often and where that basal machinery acts on higher eukaryotic chromosomes. One important mechanism for regulating the frequency and distribution of meiotic recombination is crossover interference - or the ability of one recombination event to influence nearby events. The MUS81 gene is thought to play an important role in regulating the influence of interference on crossing over. The immediate goals of this project are to use reverse genetics to identify mutants in two putative MUS81 homologs in the model plant Arabidopsis thaliana, characterize those mutants and initiate a novel forward genetic screen for additional regulators of meiotic recombination. The long-term goal of the project is to understand how meiotic recombination is regulated in higher eukaryotes with an emphasis on the molecular basis of crossover interference. The ability to monitor recombination in all four meiotic products (tetrad analysis) has been a powerful tool in the arsenal of yeast geneticists. Previously, the qrt mutant of Arabidopsis, which causes the four pollen products of male meiosis to remain attached, was developed as a facile system

  3. Gateway Recombinational Cloning.

    Science.gov (United States)

    Reece-Hoyes, John S; Walhout, Albertha J M

    2018-01-02

    The Gateway recombinatorial cloning system was developed for cloning multiple DNA fragments in parallel (e.g., in 96-well formats) in a standardized manner using the same enzymes. Gateway cloning is based on the highly specific integration and excision reactions of bacteriophage λ into and out of the Escherichia coli genome. Because the sites of recombination (" att " sites) are much longer (25-242 bp) than restriction sites, they are extremely unlikely to occur by chance in DNA fragments. Therefore, the same recombination enzyme can be used to robustly clone many different fragments of variable size in parallel reactions. © 2018 Cold Spring Harbor Laboratory Press.

  4. Landing gear noise attenuation

    Science.gov (United States)

    Moe, Jeffrey W. (Inventor); Whitmire, Julia (Inventor); Kwan, Hwa-Wan (Inventor); Abeysinghe, Amal (Inventor)

    2011-01-01

    A landing gear noise attenuator mitigates noise generated by airframe deployable landing gear. The noise attenuator can have a first position when the landing gear is in its deployed or down position, and a second position when the landing gear is in its up or stowed position. The noise attenuator may be an inflatable fairing that does not compromise limited space constraints associated with landing gear retraction and stowage. A truck fairing mounted under a truck beam can have a compliant edge to allow for non-destructive impingement of a deflected fire during certain conditions.

  5. The relationship between patient activation, confidence to self-manage side effects, and adherence to oral oncolytics: a pilot study with Michigan oncology practices.

    Science.gov (United States)

    Salgado, Teresa M; Mackler, Emily; Severson, Jane A; Lindsay, Jamie; Batra, Peter; Petersen, Laura; Farris, Karen B

    2017-06-01

    The Michigan Oncology Quality Consortium (MOQC) is a continuous quality improvement collaborative seeking to improve oncology care in Michigan, including for patients taking oral chemotherapy. The aim of this study was to assess the relationship between patient activation, confidence to self-manage side effects, and adherence to oral oncolytics to inform future oncology care. A multicenter cross-sectional observational study was conducted using an online survey to examine patient activation (patient activation measure, PAM), health literacy, symptom burden (Edmonton Symptom Assessment System, ESAS), confidence to self-manage side effects (fatigue, nausea, and diarrhea), and adherence to oral oncolytics. Inclusion criteria were patients taking an oral oncolytic for at least 1 month. Bivariate analyses and logistic regression were performed to evaluate relationships between the variables. A total of 125 respondents, mean (SD) age 66.2 (13.6), 57.7% female, and 95.1% Caucasian completed the survey. The mean (SD) PAM score was 65.0 (18.0). Confidence to manage fatigue, nausea, and diarrhea was associated with higher activation, and confidence to self-manage fatigue and diarrhea were associated with higher health literacy. About 30% of participants reported some level of non-adherence to oral oncolytics, and those who experienced side effects (Fisher's exact test p = 0.033) and with shorter length of therapy (t test p = 0.027) were significantly more likely to be non-adherent. These findings show that there is room for improvement across practices involved with MOQC with regard to supporting patients taking oral oncolytics. Patients will need to improve their activation levels, and oncology clinics will need to create new workflows in order to enhance self-care management ability for patients taking oral oncolytics.

  6. Deletion ofF4L(ribonucleotide reductase) in vaccinia virus produces a selective oncolytic virus and promotes anti-tumor immunity with superior safety in bladder cancer models.

    Science.gov (United States)

    Potts, Kyle G; Irwin, Chad R; Favis, Nicole A; Pink, Desmond B; Vincent, Krista M; Lewis, John D; Moore, Ronald B; Hitt, Mary M; Evans, David H

    2017-05-01

    Bladder cancer has a recurrence rate of up to 80% and many patients require multiple treatments that often fail, eventually leading to disease progression. In particular, standard of care for high-grade disease, Bacillus Calmette-Guérin (BCG), fails in 30% of patients. We have generated a novel oncolytic vaccinia virus (VACV) by mutating the F4L gene that encodes the virus homolog of the cell-cycle-regulated small subunit of ribonucleotide reductase (RRM2). The F4L -deleted VACVs are highly attenuated in normal tissues, and since cancer cells commonly express elevated RRM2 levels, have tumor-selective replication and cell killing. These F4L -deleted VACVs replicated selectively in immune-competent rat AY-27 and xenografted human RT112-luc orthotopic bladder cancer models, causing significant tumor regression or complete ablation with no toxicity. It was also observed that rats cured of AY-27 tumors by VACV treatment developed anti-tumor immunity as evidenced by tumor rejection upon challenge and by ex vivo cytotoxic T-lymphocyte assays. Finally, F4L -deleted VACVs replicated in primary human bladder cancer explants. Our findings demonstrate the enhanced safety and selectivity of F4L -deleted VACVs, with application as a promising therapy for patients with BCG-refractory cancers and immune dysregulation. © 2017 The Authors. Published under the terms of the CC BY 4.0 license.

  7. Expression of RNA interference triggers from an oncolytic herpes simplex virus results in specific silencing in tumour cells in vitro and tumours in vivo

    Directory of Open Access Journals (Sweden)

    Anesti Anna-Maria

    2010-09-01

    Full Text Available Abstract Background Delivery of small interfering RNA (siRNA to tumours remains a major obstacle for the development of RNA interference (RNAi-based therapeutics. Following the promising pre-clinical and clinical results with the oncolytic herpes simplex virus (HSV OncoVEXGM-CSF, we aimed to express RNAi triggers from oncolytic HSV, which although has the potential to improve treatment by silencing tumour-related genes, was not considered possible due to the highly oncolytic properties of HSV. Methods To evaluate RNAi-mediated silencing from an oncolytic HSV backbone, we developed novel replicating HSV vectors expressing short-hairpin RNA (shRNA or artificial microRNA (miRNA against the reporter genes green fluorescent protein (eGFP and β-galactosidase (lacZ. These vectors were tested in non-tumour cell lines in vitro and tumour cells that are moderately susceptible to HSV infection both in vitro and in mice xenografts in vivo. Silencing was assessed at the protein level by fluorescent microscopy, x-gal staining, enzyme activity assay, and western blotting. Results Our results demonstrate that it is possible to express shRNA and artificial miRNA from an oncolytic HSV backbone, which had not been previously investigated. Furthermore, oncolytic HSV-mediated delivery of RNAi triggers resulted in effective and specific silencing of targeted genes in tumour cells in vitro and tumours in vivo, with the viruses expressing artificial miRNA being comprehensibly more effective. Conclusions This preliminary data provide the first demonstration of oncolytic HSV-mediated expression of shRNA or artificial miRNA and silencing of targeted genes in tumour cells in vitro and in vivo. The vectors developed in this study are being adapted to silence tumour-related genes in an ongoing study that aims to improve the effectiveness of oncolytic HSV treatment in tumours that are moderately susceptible to HSV infection and thus, potentially improve response rates seen

  8. Pharmacokinetic study of neural stem cell-based cell carrier for oncolytic virotherapy: Targeted delivery of the therapeutic payload in an orthotopic brain tumor model

    OpenAIRE

    Thaci, Bart; Ahmed, Atique U.; Ulasov, Ilya V.; Tobias, Alex L.; Han, Yu; Aboody, Karen S.; Lesniak, Maciej S.

    2012-01-01

    Oncolytic virotherapy is a promising novel therapy for glioblastoma that needs to be optimized before introduced to clinic. The targeting of conditionally replicating adenoviruses (CRAds) can be improved by relying on the tumor tropic properties of neural stem cells (NSCs). Here, we report the characterization of an FDA approved NSC, HB1.F3-CD, as a cell carrier for CRAd-S-pk7, a glioma-tropic oncolytic adenovirus. We show that NSCs replicate and release infectious CRAd-S-pk7 progeny capable ...

  9. Recent advances in vesicular stomatitis virus-based oncolytic virotherapy: a 5-year update.

    Science.gov (United States)

    Felt, Sébastien A; Grdzelishvili, Valery Z

    2017-11-16

    Oncolytic virus (OV) therapy is an anti-cancer approach that uses viruses that preferentially infect, replicate in and kill cancer cells. Vesicular stomatitis virus (VSV, a rhabdovirus) is an OV that is currently being tested in the USA in several phase I clinical trials against different malignancies. Several factors make VSV a promising OV: lack of pre-existing human immunity against VSV, a small and easy to manipulate genome, cytoplasmic replication without risk of host cell transformation, independence of cell cycle and rapid growth to high titres in a broad range of cell lines facilitating large-scale virus production. While significant advances have been made in VSV-based OV therapy, room for improvement remains. Here we review recent studies (published in the last 5 years) that address 'old' and 'new' challenges of VSV-based OV therapy. These studies focused on improving VSV safety, oncoselectivity and oncotoxicity; breaking resistance of some cancers to VSV; preventing premature clearance of VSV; and stimulating tumour-specific immunity. Many of these approaches were based on combining VSV with other therapeutics. This review also discusses another rhabdovirus closely related to VSV, Maraba virus, which is currently being tested in Canada in phase I/II clinical trials.

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

    Directory of Open Access Journals (Sweden)

    Zong Sheng eGuo

    2014-04-01

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

  11. Immunotherapeutic Potential of Oncolytic H-1 Parvovirus: Hints of Glioblastoma Microenvironment Conversion towards Immunogenicity

    Directory of Open Access Journals (Sweden)

    Assia L. Angelova

    2017-12-01

    Full Text Available Glioblastoma, one of the most aggressive primary brain tumors, is characterized by highly immunosuppressive microenvironment. This contributes to glioblastoma resistance to standard treatment modalities and allows tumor growth and recurrence. Several immune-targeted approaches have been recently developed and are currently under preclinical and clinical investigation. Oncolytic viruses, including the autonomous protoparvovirus H-1 (H-1PV, show great promise as novel immunotherapeutic tools. In a first phase I/IIa clinical trial (ParvOryx01, H-1PV was safe and well tolerated when locally or systemically administered to recurrent glioblastoma patients. The virus was able to cross the blood–brain (tumor barrier after intravenous infusion. Importantly, H-1PV treatment of glioblastoma patients was associated with immunogenic changes in the tumor microenvironment. Tumor infiltration with activated cytotoxic T cells, induction of cathepsin B and inducible nitric oxide (NO synthase (iNOS expression in tumor-associated microglia/macrophages (TAM, and accumulation of activated TAM in cluster of differentiation (CD 40 ligand (CD40L-positive glioblastoma regions was detected. These are the first-in-human observations of H-1PV capacity to switch the immunosuppressed tumor microenvironment towards immunogenicity. Based on this pilot study, we present a tentative model of H-1PV-mediated modulation of glioblastoma microenvironment and propose a combinatorial therapeutic approach taking advantage of H-1PV-induced microglia/macrophage activation for further (preclinical testing.

  12. Dendritic Cells in Oncolytic Virus-Based Anti-Cancer Therapy.

    Science.gov (United States)

    Kim, Youra; Clements, Derek R; Sterea, Andra M; Jang, Hyun Woo; Gujar, Shashi A; Lee, Patrick W K

    2015-12-09

    Dendritic cells (DCs) are specialized antigen-presenting cells that have a notable role in the initiation and regulation of innate and adaptive immune responses. In the context of cancer, appropriately activated DCs can induce anti-tumor immunity by activating innate immune cells and tumor-specific lymphocytes that target cancer cells. However, the tumor microenvironment (TME) imposes different mechanisms that facilitate the impairment of DC functions, such as inefficient antigen presentation or polarization into immunosuppressive DCs. These tumor-associated DCs thus fail to initiate tumor-specific immunity, and indirectly support tumor progression. Hence, there is increasing interest in identifying interventions that can overturn DC impairment within the TME. Many reports thus far have studied oncolytic viruses (OVs), viruses that preferentially target and kill cancer cells, for their capacity to enhance DC-mediated anti-tumor effects. Herein, we describe the general characteristics of DCs, focusing on their role in innate and adaptive immunity in the context of the TME. We also examine how DC-OV interaction affects DC recruitment, OV delivery, and anti-tumor immunity activation. Understanding these roles of DCs in the TME and OV infection is critical in devising strategies to further harness the anti-tumor effects of both DCs and OVs, ultimately enhancing the efficacy of OV-based oncotherapy.

  13. Intranasal Oncolytic Virotherapy with CXCR4-Enhanced Stem Cells Extends Survival in Mouse Model of Glioma.

    Science.gov (United States)

    Dey, Mahua; Yu, Dou; Kanojia, Deepak; Li, Gina; Sukhanova, Madina; Spencer, Drew A; Pituch, Katatzyna C; Zhang, Lingjiao; Han, Yu; Ahmed, Atique U; Aboody, Karen S; Lesniak, Maciej S; Balyasnikova, Irina V

    2016-09-13

    The challenges to effective drug delivery to brain tumors are twofold: (1) there is a lack of non-invasive methods of local delivery and (2) the blood-brain barrier limits systemic delivery. Intranasal delivery of therapeutics to the brain overcomes both challenges. In mouse model of malignant glioma, we observed that a small fraction of intranasally delivered neural stem cells (NSCs) can migrate to the brain tumor site. Here, we demonstrate that hypoxic preconditioning or overexpression of CXCR4 significantly enhances the tumor-targeting ability of NSCs, but without altering their phenotype only in genetically modified NSCs. Modified NSCs deliver oncolytic virus to glioma more efficiently and extend survival of experimental animals in the context of radiotherapy. Our findings indicate that intranasal delivery of stem cell-based therapeutics could be optimized for future clinical applications, and allow for safe and repeated administration of biological therapies to brain tumors and other CNS disorders. Copyright © 2016 The Author(s). Published by Elsevier Inc. All rights reserved.

  14. Human Menstrual Blood-Derived Mesenchymal Stem Cells as Potential Cell Carriers for Oncolytic Adenovirus

    Science.gov (United States)

    Rojas, L. A.; Villellas, Felip Vilardell; Soriano, Vanessa Cervera; Fajardo, C. A.; Alemany, R.

    2017-01-01

    Antitumor efficacy of systemically administered oncolytic adenoviruses (OAdv) is limited due to diverse factors such as liver sequestration, neutralizing interactions in blood, elimination by the immune system, and physical barriers in tumors. It is therefore of clinical relevance to improve OAdv bioavailability and tumor delivery. Among the variety of tumor-targeting strategies, the use of stem cells and specifically bone marrow-derived mesenchymal stem cells (BM-MSCs) is of particular interest due to their tumor tropism and immunomodulatory properties. Nonetheless, the invasive methods to obtain these cells, the low number of MSCs present in the bone marrow, and their restricted in vitro expansion represent major obstacles for their use in cancer treatments, pointing out the necessity to identify an alternative source of MSCs. Here, we have evaluated the use of menstrual blood-derived mesenchymal stem cells (MenSCs) as cell carriers for regional delivery of an OAdv in the tumor. Our results indicate that MenSCs can be isolated without invasive methods, they have an increased proliferation rate compared to BM-MSCs, and they can be efficiently infected with different serotype 5-based capsid-modified adenoviruses, leading to viral replication and release. In addition, our in vivo studies confirmed the tumor-homing properties of MenSCs after regional administration. PMID:28781596

  15. Histone deacetylase inhibitors improve the replication of oncolytic herpes simplex virus in breast cancer cells.

    Directory of Open Access Journals (Sweden)

    James J Cody

    Full Text Available New therapies are needed for metastatic breast cancer patients. Oncolytic herpes simplex virus (oHSV is an exciting therapy being developed for use against aggressive tumors and established metastases. Although oHSV have been demonstrated safe in clinical trials, a lack of sufficient potency has slowed the clinical application of this approach. We utilized histone deacetylase (HDAC inhibitors, which have been noted to impair the innate antiviral response and improve gene transcription from viral vectors, to enhance the replication of oHSV in breast cancer cells. A panel of chemically diverse HDAC inhibitors were tested at three different doses (LD50 for their ability to modulate the replication of oHSV in breast cancer cells. Several of the tested HDAC inhibitors enhanced oHSV replication at low multiplicity of infection (MOI following pre-treatment of the metastatic breast cancer cell line MDA-MB-231 and the oHSV-resistant cell line 4T1, but not in the normal breast epithelial cell line MCF10A. Inhibitors of class I HDACs, including pan-selective compounds, were more effective for increasing oHSV replication compared to inhibitors that selectively target class II HDACs. These studies demonstrate that select HDAC inhibitors increase oHSV replication in breast cancer cells and provides support for pre-clinical evaluation of this combination strategy.

  16. Oncolytic vaccinia virus as an adjuvant treatment to cytoreductive surgery for malignant peritoneal mesothelioma.

    Science.gov (United States)

    Acuna, Sergio A; Ottolino-Perry, Kathryn; Çako, Besmira; Tang, Nan; Angarita, Fernando A; McCart, J Andrea

    2014-07-01

    Malignant peritoneal mesothelioma (MPM) is an aggressive cancer with a dismal prognosis. Oncolytic viruses are a promising new therapy for cancer because of their ability to kill tumor cells with minimal toxicity to normal tissues. This experimental study aimed to examine the potential of modified vaccinia virus (VV) to treat MPM when administered alone or as an adjuvant treatment to surgery. Two aggressive murine mesothelioma cell lines (AC29, AB12), were used. Cell viability and viral cytopathic effects were assessed using MTS and crystal violet assays. Immunocompetent mice were injected intraperitoneally with MPM cells and treated with intraperitoneal VV. Tumor-bearing mice also underwent cytoreductive surgery (CRS) followed by VV (or control) therapy. The cytotoxic effects of VV on MPM cell lines was significantly increased compared with the control non-cancer cell line. In both orthotopic models, VV induced tumor regression, prolonging median and long-term survival. VV treatment after incomplete CRS was not superior to VV alone; however, when mice with microscopic disease were treated with VV, further prolongation of median and long-term survivals was observed. VV selectively kills MPM cells in vitro and leads to improved survival and cures in immunocompetent murine models. Higher efficacy of the virus in the microscopic disease context suggests the use of the virus as an adjuvant treatment to complete surgical resection. These promising results justify further studies of VV in humans as a novel treatment for MPM.

  17. Oncolytic E1B 55KDa-deleted adenovirus replication is independent of p53 levels in cancer cells.

    Science.gov (United States)

    Abbas, B M; El-Mogy, M A; Haj-Ahmad, Y

    2017-08-15

    Oncolytic adenoviruses represent a new approach for cancer therapy due to its tumor specificity. E1B 55kDa-deleted adenovirus type 5 (Ad5dlE1B 55kDa) is a promising therapeutic agent that can selectively replicate in and lyse p53 defective cancer cells. However, the overall efficacy has shown varying degrees of success with raised doubts about the correlation between p53 status and E1B-deleted adenovirus replication ability. In this study, we investigated the relationship between the efficiency of Ad5dlE1B 55kDa replication and p53 levels in cancer cells. Five transient p53 expression vectors were engineered to expresses different p53 levels in transfected cells. Then, the effect of the variable p53 levels and cellular backgrounds on the replication efficiency of oncolytic Ad5dlE1B 55kDa was evaluated in H1299 and HeLa cell lines. We found that the replication efficiency of these oncolytic viruses is dependent on the status, but not the expression levels, of p53. Ad5dlE1B 55kDa was shown to have selective replication activity in H1299 cells (p53-null) and decreased viral replication in HeLa cells (p53-positive), relative to the wild-type adenovirus in both cell lines. Our findings suggest that there is a relation between the E1B-deleted adenovirus replication and the presence as well as the activity of p53, independent of its quantity.

  18. In vivo and in situ programming of tumor immunity by combining oncolytics and PD-1 immune checkpoint blockade.

    Science.gov (United States)

    Bartee, Eric; Li, Zihai

    2017-01-01

    Blockade of the programmed cell death protein 1 (PD1) pathway is clinically effective against human cancers. Although multiple types of malignancies have been shown to respond to PD1 agents, only a small percentage of patients typically benefit from this treatment. In addition, PD1 therapy often causes serious immune-related adverse events. A recent study demonstrated that local, intra-tumoral, administration of modified oncolytic myxoma virus which expresses a truncated version of the PD1 protein resulted in both increased efficacy and reduced toxicity in a clinically relevant melanoma model.

  19. Site directed recombination

    Science.gov (United States)

    Jurka, Jerzy W.

    1997-01-01

    Enhanced homologous recombination is obtained by employing a consensus sequence which has been found to be associated with integration of repeat sequences, such as Alu and ID. The consensus sequence or sequence having a single transition mutation determines one site of a double break which allows for high efficiency of integration at the site. By introducing single or double stranded DNA having the consensus sequence flanking region joined to a sequence of interest, one can reproducibly direct integration of the sequence of interest at one or a limited number of sites. In this way, specific sites can be identified and homologous recombination achieved at the site by employing a second flanking sequence associated with a sequence proximal to the 3'-nick.

  20. Nonradiative recombination in semiconductors

    CERN Document Server

    Abakumov, VN; Yassievich, IN

    1991-01-01

    In recent years, great progress has been made in the understandingof recombination processes controlling the number of excessfree carriers in semiconductors under nonequilibrium conditions. As a result, it is now possible to give a comprehensivetheoretical description of these processes. The authors haveselected a number of experimental results which elucidate theunderlying physical problems and enable a test of theoreticalmodels. The following topics are dealt with: phenomenological theory ofrecombination, theoretical models of shallow and deep localizedstates, cascade model of carrier captu

  1. Radiofrequency attenuator and method

    Science.gov (United States)

    Warner, Benjamin P [Los Alamos, NM; McCleskey, T Mark [Los Alamos, NM; Burrell, Anthony K [Los Alamos, NM; Agrawal, Anoop [Tucson, AZ; Hall, Simon B [Palmerston North, NZ

    2009-01-20

    Radiofrequency attenuator and method. The attenuator includes a pair of transparent windows. A chamber between the windows is filled with molten salt. Preferred molten salts include quarternary ammonium cations and fluorine-containing anions such as tetrafluoroborate (BF.sub.4.sup.-), hexafluorophosphate (PF.sub.6.sup.-), hexafluoroarsenate (AsF.sub.6.sup.-), trifluoromethylsulfonate (CF.sub.3SO.sub.3.sup.-), bis(trifluoromethylsulfonyl)imide ((CF.sub.3SO.sub.2).sub.2N.sup.-), bis(perfluoroethylsulfonyl)imide ((CF.sub.3CF.sub.2SO.sub.2).sub.2N.sup.-) and tris(trifluoromethylsulfonyl)methide ((CF.sub.3SO.sub.2).sub.3C.sup.-). Radicals or radical cations may be added to or electrochemically generated in the molten salt to enhance the RF attenuation.

  2. Type III IFN interleukin-28 mediates the antitumor efficacy of oncolytic virus VSV in immune-competent mouse models of cancer.

    Science.gov (United States)

    Wongthida, Phonphimon; Diaz, Rosa Maria; Galivo, Feorillo; Kottke, Timothy; Thompson, Jill; Pulido, Jose; Pavelko, Kevin; Pease, Larry; Melcher, Alan; Vile, Richard

    2010-06-01

    Innate immune effector mechanisms triggered by oncolytic viruses may contribute to the clearance of both infected and uninfected tumor cells in immunocompetent murine hosts. Here, we developed an in vitro tumor cell/bone marrow coculture assay and used it to dissect innate immune sensor and effector responses to intratumoral vesicular stomatitis virus (VSV). We found that the type III IFN interleukin-28 (IL-28) was induced by viral activation of innate immune-sensing cells, acting as a key mediator of VSV-mediated virotherapy of B16ova melanomas. Using tumor variants which differentially express the IL-28 receptor, we showed that IL-28 induced by VSV within the tumor microenvironment sensitizes tumor cells to natural killer cell recognition and activation. These results revealed new insights into the immunovirological mechanisms associated with oncolytic virotherapy in immune-competent hosts. Moreover, they defined a new class of tumor-associated mutation, such as acquired loss of responsiveness to IL-28 signaling, which confers insensitivity to oncolytic virotherapy through a mechanism independent of viral replication in vitro. Lastly, the findings suggested new strategies to manipulate immune signals that may enhance viral replication, along with antitumor immune activation, and improve the efficacy of oncolytic virotherapies. Copyright 2010 AACR.

  3. Comparison of the E3 and L3 regions for arming oncolytic adenoviruses to achieve a high level of tumor-specific transgene expression.

    Science.gov (United States)

    Robinson, M; Ge, Y; Ko, D; Yendluri, S; Laflamme, G; Hawkins, L; Jooss, K

    2008-01-01

    Arming oncolytic adenoviral vectors with anticancer transgenes that can be expressed in a tumor-selective manner may enable the engineering of vectors with increased potency, while retaining their safety profile. Armed oncolytic adenoviral vectors were constructed in which transgene expression has been linked via modified splice acceptor sequences that did not necessitate the deletion of any part of the adenoviral genome. Several oncolytic adenoviral vectors were compared in which the transgene was inserted in place of either the E3 or the L3 region. While all vectors had similar viral growth and cytotoxicity characteristics, the highest level of transgene expression was observed from a vector in which the transgene had been inserted downstream of the L3 23K protease gene, the Ad-23K-GM vector. Notably, no transgene expression occurred with this vector in the absence of DNA replication either in vitro or in vivo. In contrast, viruses in which the transgene was inserted into E3 locations exhibited a low level of transgene expression even in the absence of DNA replication. In summary, by utilizing the L3 region for arming oncolytic viruses, higher levels of tumor-specific transgene expression can be obtained without the need to delete any parts of the viral genome.

  4. IL-12 Expressing oncolytic herpes simplex virus promotes anti-tumor activity and immunologic control of metastatic ovarian cancer in mice.

    Science.gov (United States)

    Thomas, Eric D; Meza-Perez, Selene; Bevis, Kerri S; Randall, Troy D; Gillespie, G Yancey; Langford, Catherine; Alvarez, Ronald D

    2016-10-27

    Despite advances in surgical aggressiveness and conventional chemotherapy, ovarian cancer remains the most lethal cause of gynecologic cancer mortality; consequently there is a need for new therapeutic agents and innovative treatment paradigms for the treatment of ovarian cancer. Several studies have demonstrated that ovarian cancer is an immunogenic disease and immunotherapy represents a promising and novel approach that has not been completely evaluated in ovarian cancer. Our objective was to evaluate the anti-tumor activity of an oncolytic herpes simplex virus "armed" with murine interleukin-12 and its ability to elicit tumor-specific immune responses. We evaluated the ability of interleukin-12-expressing and control oncolytic herpes simplex virus to kill murine and human ovarian cancer cell lines in vitro. We also administered interleukin-12-expressing oncolytic herpes simplex virus to the peritoneal cavity of mice that had developed spontaneous, metastatic ovarian cancer and determined overall survival and tumor burden at 95 days. We used flow cytometry to quantify the tumor antigen-specific CD8 + T cell response in the omentum and peritoneal cavity. All ovarian cancer cell lines demonstrated susceptibility to oncolytic herpes simplex virus in vitro. Compared to controls, mice treated with interleukin-12-expressing oncolytic herpes simplex virus demonstrated a more robust tumor antigen-specific CD8 + T-cell immune response in the omentum (471.6 cells vs 33.1 cells; p = 0.02) and peritoneal cavity (962.3 cells vs 179.5 cells; p = 0.05). Compared to controls, mice treated with interleukin-12-expressing oncolytic herpes simplex virus were more likely to control ovarian cancer metastases (81.2 % vs 18.2 %; p = 0.008) and had a significantly longer overall survival (p = 0.02). Finally, five of 6 mice treated with interleukin-12-expressing oHSV had no evidence of metastatic tumor when euthanized at 6 months, compared to two of 4 mice treated with

  5. Molecular Determinants of Susceptibility to Oncolytic Vesicular Stomatitis Virus in Pancreatic Adenocarcinoma

    Science.gov (United States)

    Blackham, Aaron U; Northrup, Scott A; Willingham, Mark; Sirintrapun, Joseph; Russell, Greg B; Lyles, Douglas S; Stewart, John H

    2014-01-01

    Background M protein mutant vesicular stomatitis virus (M51R-VSV) has oncolytic properties against many cancers. However, some cancer cells are resistant to M51R-VSV. Herein, we evaluate the molecular determinants of VSV resistance in pancreatic adenocarcinoma cells. Methods Cell viability and the effect of β-interferon (IFN) was analyzed using MTS assay. Gene expression was evaluated via microarray analysis. Cell infectability was measured by flow cytometry. Xenografts were established in athymic nude mice and treated with intratumoral M51R-VSV. Results Four of five pancreatic cancer cell lines were sensitive to M51R-VSV, while Panc03.27 cells remained resistant (81±3% viability 72-hours after single cycle infection). Comparing sensitive MiaPaCa2 to resistant Panc03.27 cells, significant differences in gene expression was found relating to IFN signaling (p=2×10-5), viral entry (p=3×10-4) and endocytosis (p=7×10-4). MiaPaCa2 cells permitted high levels of VSV infection, while Panc03.27 cells were capable of resisting VSV cell entry even at high MOIs. Extrinsic β-IFN overcame apparent defects in IFN-mediated pathways in MiaPaCa2 cells conferring VSV resistance. In contrast, β-IFN decreased cell viability in Panc3.27 cells suggesting intact anti-viral mechanisms. VSV treated xenografts exhibited reduced tumor growth relative to controls in both MiaPaCa2 (1423 ± 345% vs 164 ± 136%, pVSV treated Panc03.27 xenografts. Conclusions Inhibition of VSV endocytosis and intact IFN-mediated defenses are responsible for M51R-VSV resistance in pancreatic adenocarcinoma cells. M51R-VSV treatment appears to induce anti-tumor cellular immunity in vivo which may expand its clinical efficacy. PMID:24252853

  6. Oncolytic adenoviruses targeted to Human Papilloma Virus-positive head and neck squamous cell carcinomas.

    Science.gov (United States)

    LaRocca, Christopher J; Han, Joohee; Salzwedel, Amanda O; Davydova, Julia; Herzberg, Mark C; Gopalakrishnan, Rajaram; Yamamoto, Masato

    2016-05-01

    In recent years, the incidence of Human Papilloma Virus (HPV)-positive head and neck squamous cell carcinomas (HNSCC) has markedly increased. Our aim was to design a novel therapeutic agent through the use of conditionally replicative adenoviruses (CRAds) that are targeted to the HPV E6 and E7 oncoproteins. Each adenovirus included small deletion(s) in the E1a region of the genome (Δ24 or CB016) intended to allow for selective replication in HPV-positive cells. In vitro assays were performed to analyze the transduction efficiency of the vectors and the cell viability following viral infection. Then, the UPCI SCC090 cell line (HPV-positive) was used to establish subcutaneous tumors in the flanks of nude mice. The tumors were then treated with either one dose of the virus or four doses (injected every fourth day). The transduction analysis with luciferase-expressing viruses demonstrated that the 5/3 fiber modification maximized virus infectivity. In vitro, both viruses (5/3Δ24 and 5/3CB016) demonstrated profound oncolytic effects. The 5/3CB016 virus was more selective for HPV-positive HNSCC cells, whereas the 5/3Δ24 virus killed HNSCC cells regardless of HPV status. In vivo, single injections of both viruses demonstrated anti-tumor effects for only a few days following viral inoculation. However, after four viral injections, there was statistically significant reductions in tumor growth when compared to the control group (p<0.05). CRAds targeted to HPV-positive HNSCCs demonstrated excellent in vitro and in vivo therapeutic effects, and they have the potential to be clinically translated as a novel treatment modality for this emerging disease. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. Semireplication-competent vesicular stomatitis virus as a novel platform for oncolytic virotherapy.

    Science.gov (United States)

    Muik, Alexander; Dold, Catherine; Geiß, Yvonne; Volk, Andreas; Werbizki, Marina; Dietrich, Ursula; von Laer, Dorothee

    2012-08-01

    Among oncolytic viruses, the vesicular stomatitis virus (VSV) is especially potent and a highly promising agent for the treatment of cancer. But, even though effective against multiple tumor entities in preclinical animal models, replication-competent VSV exhibits inherent neurovirulence, which has so far hindered clinical development. To overcome this limitation, replication-defective VSV vectors for cancer gene therapy have been tested and proven to be safe. However, gene delivery was inefficient and only minor antitumor efficacy was observed. Here, we present semireplication-competent vector systems for VSV (srVSV), composed of two trans-complementing, propagation-deficient VSV vectors. The de novo generated deletion mutants of the two VSV polymerase proteins P (phosphoprotein) and L (large catalytic subunit), VSVΔP and VSVΔL respectively, were used mutually or in combination with VSVΔG vectors. These srVSV systems copropagated in vitro and in vivo without recombinatory reversion to replication-competent virus. The srVSV systems were highly lytic for human glioblastoma cell lines, spheroids, and subcutaneous xenografts. Especially the combination of VSVΔG/VSVΔL vectors was as potent as wild-type VSV (VSV-WT) in vitro and induced long-term tumor regression in vivo without any associated adverse effects. In contrast, 90% of VSV-WT-treated animals succumbed to neurological disease shortly after tumor clearance. Most importantly, even when injected into the brain, VSVΔG/VSVΔL did not show any neurotoxicity. In conclusion, srVSV is a promising platform for virotherapeutic approaches and also for VSV-based vector vaccines, combining improved safety with an increased coding capacity for therapeutic transgenes, potentially allowing for multipronged approaches.

  8. Taming the Trojan horse: optimizing dynamic carrier cell/oncolytic virus systems for cancer biotherapy.

    Science.gov (United States)

    Power, A T; Bell, J C

    2008-05-01

    Live cells offer unique advantages as vehicles for systemic oncolytic virus (OV) delivery. Recent studies from our laboratory and others have shown that virus-infected cells can serve as Trojan horse vehicles to evade antiviral mechanisms encountered in the bloodstream, prevent uptake by off-target tissues and act as microscale factories to produce OV upon arrival in tumor beds. However to be employed effectively, OV-infected cells are best viewed as dynamic biological systems rather than static therapeutic agents. The time-dependent processes of infection and in vivo cell trafficking will inevitably vary depending on which particular OV is being delivered, as well as the type of carrier cells (CC) employed. Understanding these parameters with respect to each unique CC/OV combination will therefore be required in order to effectively evaluate and harness their potential in preclinical study. In the following review, we discuss how early studies of OV delivery led us to investigate the use of cell carriers in our laboratory, and the approaches we are currently undertaking to compare the dynamics of different CC/OV systems. On the basis of these studies and others it is apparent that the success of any cell-based system for OV delivery rests upon the coordinated timing of three sequential phases--(1) ex vivo loading, (2) stealth delivery and (3) virus production at the tumor site. While at the current time, the timing of these processes are coupled to the natural cycle of infection and in vivo trafficking properties innate to each cell virus system, a quantitative delineation of their dynamics will lay the foundation for engineering CC/OV biotherapeutic systems that can be clinically deployed in a highly directed and controlled manner.

  9. Enhanced T Cell-Mediated Protection against Malaria in Human Challenges by Using the Recombinant Poxviruses FP9 and Modified Vaccinia virus Ankara

    National Research Council Canada - National Science Library

    Daniel P. Webster; Susanna Dunachie; Jenni M. Vuola; Tamara Berthoud; Sheila Keating; Stephen M. Laidlaw; Samuel J. McConkey; Ian Poulton; Laura Andrews; Rikke F. Andersen; Philip Bejon; Geoff Butcher; Robert Sinden; Michael A. Skinner; Sarah C. Gilbert; Adrian V. S. Hill; Louis H. Miller

    2005-01-01

    .... Here, we report that substitution of plasmid DNA as the priming vector with a specific attenuated recombinant fowlpox virus, FP9, vaccine in such prime-boost regimes can elicit complete sterile...

  10. A pRb-responsive, RGD-modified, and Hyaluronidase-armed Canine Oncolytic Adenovirus for Application in Veterinary Oncology

    Science.gov (United States)

    Laborda, Eduardo; Puig-Saus, Cristina; Rodriguez-García, Alba; Moreno, Rafael; Cascalló, Manel; Pastor, Josep; Alemany, Ramon

    2014-01-01

    Human and canine cancer share similarities such as genetic and molecular aspects, biological complexity, tumor epidemiology, and targeted therapeutic treatment. Lack of good animal models for human adenovirotherapy has spurred the use of canine adenovirus 2-based oncolytic viruses. We have constructed a canine oncolytic virus that mimics the characteristics of our previously published human adenovirus ICOVIR17: expression of E1a controlled by E2F sites, deletion of the pRb-binding site of E1a, insertion of an RGD integrin-binding motif at the fiber Knob, and expression of hyaluronidase under the major late promoter/IIIa protein splicing acceptor control. Preclinical studies showed selectivity, increased cytotoxicity, and strong hyaluronidase activity. Intratumoral treatment of canine osteosarcoma and melanoma xenografts in mice resulted in inhibition of tumor growth and prolonged survival. Moreover, we treated six dogs with different tumor types, including one adenoma, two osteosarcomas, one mastocitoma, one fibrosarcoma, and one neuroendocrine hepatic carcinoma. No virus-associated adverse effects were observed, but toxicity associated to tumor lysis, including disseminated intravascular coagulation and systemic failure, was found in one case. Two partial responses and two stable diseases warrant additional clinical testing. PMID:24448161

  11. Prevention of EBV lymphoma development by oncolytic myxoma virus in a murine xenograft model of post-transplant lymphoproliferative disease

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Manbok, E-mail: manbok66@dankook.ac.kr [Department of Molecular Genetics and Microbiology, University of Florida, Gainesville, FL 32610 (United States); Rahman, Masmudur M. [Department of Molecular Genetics and Microbiology, University of Florida, Gainesville, FL 32610 (United States); Cogle, Christopher R. [Department of Hematology/Oncology, University of Florida, Gainesville, FL 32610 (United States); McFadden, Grant [Department of Molecular Genetics and Microbiology, University of Florida, Gainesville, FL 32610 (United States)

    2015-07-10

    Epstein–Barr virus (EBV) has been associated with a variety of epithelial and hematologic malignancies, including B-, T- and NK cell-lymphomas, Hodgkin's disease (HD), post-transplant lymphoproliferative diseases (LPDs), nasopharyngeal and gastric carcinomas, smooth muscle tumors, and HIV-associated lymphomas. Currently, treatment options for EBV-associated malignancies are limited. We have previously shown that myxoma virus specifically targets various human solid tumors and leukemia cells in a variety of animal models, while sparing normal human or murine tissues. Since transplant recipients of bone marrow or solid organs often develop EBV-associated post-transplant LPDs and lymphoma, myxoma virus may be of utility to prevent EBV-associated malignancies in immunocompromised transplant patients where treatment options are frequently limited. In this report, we demonstrate the safety and efficacy of myxoma virus purging as a prophylactic strategy for preventing post-transplant EBV-transformed human lymphomas, using a highly immunosuppressed mouse xenotransplantation model. This provides support for developing myxoma virus as a potential oncolytic therapy for preventing EBV-associated LPDs following transplantation of bone marrow or solid organ allografts. - Highlights: • Myxoma virus effectively infects and purges EBV lymphoma cells in vivo. • Oncolytic myxoma virus effectively eradicates oncogenic EBV tumorigenesis. • Ex vivo pre-treatment of myxoma virus can be effective as a preventive treatment modality for post-transplant lymphoproliferative diseases.

  12. A cancer-favoring oncolytic vaccinia virus shows enhanced suppression of stem-cell like colon cancer.

    Science.gov (United States)

    Yoo, So Young; Bang, Seo Young; Jeong, Su-Nam; Kang, Dae Hwan; Heo, Jeong

    2016-03-29

    Stem cell-like colon cancer cells (SCCs) pose a major challenge in colon cancer treatment because of their resistance to chemotherapy and radiotherapy. Oncolytic virus-based therapy has shown promising results in uncured cancer patients; however, its effects on SCCs are not well studied yet. Here, we engineered a cancer-favoring oncolytic vaccinia virus (CVV) as a potent biotherapeutic and investigated its therapeutic efficacy in terms of killing SCCs. CVV is an evolved Wyeth strain vaccinia virus (EVV) lacking the viral thymidine kinase. SCC models were established using human or mouse colon cancer spheres, which continuously expressed stemness markers. The cancer-favoring characteristics and different cytotoxic pathways for killing cancer cells successfully overrode general drug resistance, thereby killing colon cancer cells regardless of the presence of SCCs. Subcutaneously injected HT29 spheres showed lower growth in CVV-treated models than in 5-Fu-treated models. Intraperitoneally injected CT26 spheres induced tumor masses in the abdominal region. CVV-treated groups showed higher survival rates and smaller tumor mass formation, compared to 5-Fu-treated groups. Interestingly, the combined treatment of CVV with 5-Fu showed improved survival rates and complete suppression of tumor mass. The CVV developed in this study, thus, effectively suppresses SCCs, which can be synergistically enhanced by simultaneous treatment with the anticancer drug 5-Fu. Our novel CVV is highly advantageous as a next-generation therapeutic for treating colon cancer.

  13. Navigating the clinical development landscape for oncolytic viruses and other cancer therapeutics: no shortcuts on the road to approval.

    Science.gov (United States)

    Breitbach, Caroline J; Reid, Tony; Burke, James; Bell, John C; Kirn, David H

    2010-01-01

    Chemotherapy remains a common mode of anticancer treatment even though in most cancer indications the therapeutic approach is not effective and ultimately associated with the onset of chemoresistance. A better understanding of genetic differences in tumors ushered in the era of targeted therapy which has revolutionized the treatment of certain cancer types. However, generally targeted therapies are only cytostatic and a proportion of the patient population may be non-responsive to targeted therapy due to mutations of other genes in the same pathway (e.g. ras mutations in patients with colorectal cancer treated with EGFR targeted therapy). Therefore, there exists a need for a radically new approach to cancer therapy. Oncolytic viruses (OVs) possess many properties of an ideal cancer therapeutic. OVs are cytotoxic and target cancers via multiple mechanisms of action while at the same time exploiting validated genetic pathways known to be dysregulated in many cancers. Indeed, promising safety and efficacy data has emerged from Phase 1 and Phase 2 trials with diverse OVs (e.g. JX-594, a targeted oncolytic poxvirus). Though the field has lagged behind with pivotal, randomized Phase 3 trials, these are currently being initiated for a number of OVs. In addition, the field must ensure a continued clinical development of newly developed OVs; a strategy for the clinical development of novel cancer therapeutics is outlined. 2010 Elsevier Ltd. All rights reserved.

  14. Myxoma virus sensitizes cancer cells to gemcitabine and is an effective oncolytic virotherapeutic in models of disseminated pancreatic cancer.

    Science.gov (United States)

    Wennier, Sonia Tusell; Liu, Jia; Li, Shoudong; Rahman, Masmudur M; Mona, Mahmoud; McFadden, Grant

    2012-04-01

    Myxoma virus (MYXV) is a novel oncolytic virus that has been shown to replicate in pancreatic cancer cells, but its efficacy in animal models of pancreatic cancer has not been determined. The efficacy of MYXV as monotherapy or in combination with gemcitabine was evaluated in intraperitoneal dissemination (IPD) models of pancreatic cancer. The effects of an intact immune system on the efficacy of MYXV therapy was tested by comparing immunodeficient versus immunocompetent murine models and combination therapy with gemcitabine was also evaluated. In cell culture, MYXV replication was robust in a broad range of pancreatic cancer cells and also showed increased oncolysis in combination with gemcitabine. In animal models, MYXV treatment conferred survival benefits over control or gemcitabine-treated cohorts regardless of the cell line or animal model used. MYXV monotherapy was most effective in an immunocompetent IPD model, and resulted in 60% long-term survivors. In Pan02 engrafted immunocompetent IPD models, sequential treatment in which MYXV was administered first, followed by gemcitabine, was the most effective and resulted in 100% long-term survivors. MYXV is an effective oncolytic virus for pancreatic cancer and can be combined with gemcitabine to enhance survival, particularly in the presence of an intact host immune system.

  15. Selective purging of human multiple myeloma cells from autologous stem cell transplantation grafts using oncolytic myxoma virus.

    Science.gov (United States)

    Bartee, Eric; Chan, Winnie M; Moreb, Jan S; Cogle, Christopher R; McFadden, Grant

    2012-10-01

    Autologous stem cell transplantation and novel therapies have improved overall survival of patients with multiple myeloma; however, most patients relapse and eventually succumb to their disease. Evidence indicates that residual cancer cells contaminate autologous grafts and may contribute to early relapses after autologous stem cell transplantation. Here, we demonstrate that ex vivo treatment with an oncolytic poxvirus called myxoma virus results in specific elimination of human myeloma cells by inducing rapid cellular apoptosis while fully sparing normal hematopoietic stem and progenitor cells. The specificity of this elimination is based on strong binding of the virus to myeloma cells coupled with an inability of the virus to bind or infect CD34(+) hematopoietic stem and progenitor cells. These 2 features allow myxoma to readily identify and distinguish even low levels of myeloma cells in complex mixtures. This ex vivo rabbit-specific oncolytic poxvirus called myxoma virus treatment also effectively inhibits systemic in vivo engraftment of human myeloma cells into immunodeficient mice and results in efficient elimination of primary CD138(+) myeloma cells contaminating patient hematopoietic cell products. We conclude that ex vivo myxoma treatment represents a safe and effective method to selectively eliminate myeloma cells from hematopoietic autografts before reinfusion. Copyright © 2012 American Society for Blood and Marrow Transplantation. Published by Elsevier Inc. All rights reserved.

  16. RGD-modifided oncolytic adenovirus exhibited potent cytotoxic effect on CAR-negative bladder cancer-initiating cells

    Science.gov (United States)

    Yang, Y; Xu, H; Shen, J; Yang, Y; Wu, S; Xiao, J; Xu, Y; Liu, X-Y; Chu, L

    2015-01-01

    Cancer-initiating cell (CIC) is critical in cancer development, maintenance and recurrence. The reverse expression pattern of coxsackie and adenovirus receptor (CAR) and αν integrin in bladder cancer decreases the infection efficiency of adenovirus. We constructed Arg-Gly-Asp (RGD)-modified oncolytic adenovirus, carrying EGFP or TNF-related apoptosis-inducing ligand (TRAIL) gene (OncoAd.RGD-hTERT-EGFP/TRAIL), and applied them to CAR-negative bladder cancer T24 cells and cancer-initiating T24 sphere cells. OncoAd.RGD-hTERT-EGFP had enhanced infection ability and cytotoxic effect on T24 cells and T24 sphere cells, but little cytoxicity on normal urothelial SV-HUC-1 cells compared with the unmodified virus OncoAd.hTERT-EGFP. Notably, OncoAd.RGD-hTERT-TRAIL induced apoptosis in T24 cells and T24 sphere cells. Furthermore, it completely inhibited xenograft initiation established by the oncolytic adenovirus-pretreated T24 sphere cells, and significantly suppressed tumor growth by intratumoral injection. These results provided a promising therapeutic strategy for CAR-negative bladder cancer through targeting CICs. PMID:25973680

  17. Bacterial Recombineering: Genome Engineering via Phage-Based Homologous Recombination.

    Science.gov (United States)

    Pines, Gur; Freed, Emily F; Winkler, James D; Gill, Ryan T

    2015-11-20

    The ability to specifically modify bacterial genomes in a precise and efficient manner is highly desired in various fields, ranging from molecular genetics to metabolic engineering and synthetic biology. Much has changed from the initial realization that phage-derived genes may be employed for such tasks to today, where recombineering enables complex genetic edits within a genome or a population. Here, we review the major developments leading to recombineering becoming the method of choice for in situ bacterial genome editing while highlighting the various applications of recombineering in pushing the boundaries of synthetic biology. We also present the current understanding of the mechanism of recombineering. Finally, we discuss in detail issues surrounding recombineering efficiency and future directions for recombineering-based genome editing.

  18. Radioiodide imaging and radiovirotherapy of multiple myeloma using VSV(Delta51)-NIS, an attenuated vesicular stomatitis virus encoding the sodium iodide symporter gene.

    Science.gov (United States)

    Goel, Apollina; Carlson, Stephanie K; Classic, Kelly L; Greiner, Suzanne; Naik, Shruthi; Power, Anthony T; Bell, John C; Russell, Stephen J

    2007-10-01

    Multiple myeloma is a radiosensitive malignancy that is currently incurable. Here, we generated a novel recombinant vesicular stomatitis virus [VSV(Delta51)-NIS] that has a deletion of methionine 51 in the matrix protein and expresses the human sodium iodide symporter (NIS) gene. VSV(Delta51)-NIS showed specific oncolytic activity against myeloma cell lines and primary myeloma cells and was able to replicate to high titers in myeloma cells in vitro. Iodide uptake assays showed accumulation of radioactive iodide in VSV(Delta51)-NIS-infected myeloma cells that was specific to the function of the NIS transgene. In bg/nd/xid mice with established subcutaneous myeloma tumors, administration of VSV(Delta51)-NIS resulted in high intratumoral virus replication and tumor regression. VSV-associated neurotoxicity was not observed. Intratumoral spread of the infection was monitored noninvasively by serial gamma camera imaging of (123)I-iodide biodistribution. Dosimetry calculations based on these images pointed to the feasibility of combination radiovirotherapy with VSV(Delta51)-NIS plus (131)I. Immunocompetent mice with syngeneic 5TGM1 myeloma tumors (either subcutaneous or orthotopic) showed significant enhancements of tumor regression and survival when VSV(Delta51)-NIS was combined with (131)I. These results show that VSV(Delta51)-NIS is a safe oncolytic agent with significant therapeutic potential in multiple myeloma.

  19. Targeting gallbladder cancer: oncolytic virotherapy with myxoma virus is enhanced by rapamycin in vitro and further improved by hyaluronan in vivo.

    Science.gov (United States)

    Weng, Mingzhe; Gong, Wei; Ma, Mingzhe; Chu, Bingfeng; Qin, Yiyu; Zhang, Mingdi; Lun, Xueqing; McFadden, Grant; Forsyth, Peter; Yang, Yong; Quan, Zhiwei

    2014-04-13

    Gallbladder carcinoma (GBC) is highly lethal, and effective treatment will require synergistic anti-tumor management. The study is aimed at investigating the oncolytic value of myxoma virus (MYXV) infection against GBC and optimizing MYXV oncolytic efficiency. We examined the permissiveness of GBC cell lines to MYXV infection and compared the effects of MYXV on cell viability among GBC and control permissive glioma cells in vitro and in vivo after MYXV + rapamycin (Rap) treatment, which is known to enhance cell permissiveness to MYXV by upregulating p-Akt levels. We also assessed MYXV + hyaluronan (HA) therapy efficiency by examinating Akt activation status, MMP-9 expression, cell viability, and collagen distribution. We further compared hydraulic conductivity, tumor area, and survival of tumor-bearing mice between the MYXV + Rap and MYXV + HA therapeutic regimens. MYXV + Rap treatment could considerably increase the oncolytic ability of MYXV against GBC cell lines in vitro but not against GBC xenografts in vivo. We found higher levels of collagen IV in GBC tumors than in glioma tumors. Diffusion analysis demonstrated that collagen IV could physically hinder MYXV intratumoral distribution. HA-CD44 interplay was found to activate the Akt signaling pathway, which increases oncolytic rates. HA was also found to enhance the MMP-9 secretion, which contributes to collagen IV degradation. Unlike MYXV + Rap, MYXV + HA therapy significantly enhanced the anti-tumor effects of MYXV in vivo and prolonged survival of GBC tumor-bearing mice. HA may optimize the oncolytic effects of MYXV on GBC via the HA-CD44 interaction which can promote viral infection and diffusion.

  20. Natural attenuation of herbicides

    DEFF Research Database (Denmark)

    Tuxen, Nina; Højberg, Anker Lajer; Broholm, Mette Martina

    2002-01-01

    A field injection experiment in a sandy, aerobic aquifer showed that two phenoxy acids MCPP (mecoprop) and dichlorprop were degraded within I in downgradient of the injection wells after an apparent lag period. The plume development and microbial measurements indicated that microbial growth....... The observations may be important for application of natural attenuation as a remedy in field scale systems....

  1. Expression of recombinant Antibodies

    Directory of Open Access Journals (Sweden)

    André eFrenzel

    2013-07-01

    Full Text Available Recombinant antibodies are highly specific detection probes in research, diagnostics and have emerged over the last two decades as the fastest growing class of therapeutic proteins. Antibody generation has been dramatically accelerated by in vitro selection systems, particularly phage display. An increasing variety of recombinant production systems have been developed, ranging from Gram-negative and positive bacteria, yeasts and filamentous fungi, insect cell lines, mammalian cells to transgenic plants and animals. Currently, almost all therapeutic antibodies are still produced in mammalian cell lines in order to reduce the risk of immunogenicity due to altered, non-human glycosylation patterns. However, recent developments of glycosylation-engineered yeast, insect cell lines and transgenic plants are promising to obtain antibodies with human-like post-translational modifications. Furthermore, smaller antibody fragments including bispecific antibodies without any glycosylation are successfully produced in bacteria and have advanced to clinical testing. The first therapeutic antibody products from a non-mammalian source can be expected in coming next years. In this review, we focus on current antibody production systems including their usability for different applications.

  2. Expression of Recombinant Antibodies

    Science.gov (United States)

    Frenzel, André; Hust, Michael; Schirrmann, Thomas

    2013-01-01

    Recombinant antibodies are highly specific detection probes in research, diagnostics, and have emerged over the last two decades as the fastest growing class of therapeutic proteins. Antibody generation has been dramatically accelerated by in vitro selection systems, particularly phage display. An increasing variety of recombinant production systems have been developed, ranging from Gram-negative and positive bacteria, yeasts and filamentous fungi, insect cell lines, mammalian cells to transgenic plants and animals. Currently, almost all therapeutic antibodies are still produced in mammalian cell lines in order to reduce the risk of immunogenicity due to altered, non-human glycosylation patterns. However, recent developments of glycosylation-engineered yeast, insect cell lines, and transgenic plants are promising to obtain antibodies with “human-like” post-translational modifications. Furthermore, smaller antibody fragments including bispecific antibodies without any glycosylation are successfully produced in bacteria and have advanced to clinical testing. The first therapeutic antibody products from a non-mammalian source can be expected in coming next years. In this review, we focus on current antibody production systems including their usability for different applications. PMID:23908655

  3. Dissociative recombination of HCl+

    Science.gov (United States)

    Larson, Åsa; Fonseca dos Santos, Samantha; E. Orel, Ann

    2017-08-01

    The dissociative recombination of HCl+, including both the direct and indirect mechanisms, is studied. For the direct process, the relevant electronic states are calculated ab initio by combining electron scattering calculations to obtain resonance positions and autoionization widths with multi-reference configuration interaction calculations of the ion and Rydberg states. The cross section for the direct dissociation along electronic resonant states is computed by solution of the time-dependent Schrödinger equation. For the indirect process, an upper bound value for the cross section is obtained using a vibrational frame transformation of the elements of the scattering matrix at energies just above the ionization threshold. Vibrational excitations of the ionic core from the ground vibrational state, v = 0 , to the first three excited vibrational states, v = 1 , v = 2 , and v = 3 , are considered. Autoionization is neglected and the effect of the spin-orbit splitting of the ionic potential energy upon the indirect dissociative recombination cross section is considered. The calculated cross sections are compared to measurements.

  4. Microbial factories for recombinant pharmaceuticals

    National Research Council Canada - National Science Library

    Ferrer-Miralles, Neus; Domingo-Espín, Joan; Corchero, José Luis; Vázquez, Esther; Villaverde, Antonio

    2009-01-01

    ...-translational modifications, proteolytic instability, poor solubility and activation of cell stress responses, among others, they represent convenient and powerful tools for recombinant protein production...

  5. Fluid dynamic bowtie attenuators

    Science.gov (United States)

    Szczykutowicz, Timothy P.; Hermus, James

    2015-03-01

    Fluence field modulated CT allows for improvements in image quality and dose reduction. To date, only 1-D modulators have been proposed, the extension to 2-D modulation is difficult with solid-metal attenuation-based modulators. This work proposes to use liquids and gas to attenuate the x-ray beam which can be arrayed allowing for 2-D fluence modulation. The thickness of liquid and the pressure for a given path length of gas were determined that provided the same attenuation as 30 cm of soft tissue at 80, 100, 120, and 140 kV. Gaseous Xenon and liquid Iodine, Zinc Chloride, and Cerium Chloride were studied. Additionally, we performed some proof-of-concept experiments in which (1) a single cell of liquid was connected to a reservoir which allowed the liquid thickness to be modulated and (2) a 96 cell array was constructed in which the liquid thickness in each cell was adjusted manually. Liquid thickness varied as a function of kV and chemical composition, with Zinc Chloride allowing for the smallest thickness; 1.8, 2.25, 3, and 3.6 cm compensated for 30 cm of soft tissue at 80, 100, 120, and 140 kV respectively. The 96 cell Iodine attenuator allowed for a reduction in both dynamic range to the detector and scatter to primary ratio. Successful modulation of a single cell was performed at 0, 90, and 130 degrees using a simple piston/actuator. The thickness of liquids and the Xenon gas pressure seem logistically implementable within the constraints of CBCT and diagnostic CT systems.

  6. Durable response rate as an endpoint in cancer immunotherapy: insights from oncolytic virus clinical trials.

    Science.gov (United States)

    Kaufman, Howard L; Andtbacka, Robert H I; Collichio, Frances A; Wolf, Michael; Zhao, Zhongyun; Shilkrut, Mark; Puzanov, Igor; Ross, Merrick

    2017-09-19

    Traditional response criteria may be insufficient to characterize full clinical benefits of anticancer immunotherapies. Consequently, endpoints such as durable response rate (DRR; a continuous response [complete or partial objective response] beginning within 12 months of treatment and lasting ≥6 months) have been employed. There has not, however, been validation that DRR correlates with other more traditional endpoints of clinical benefit such as overall survival. We evaluated whether DRR was associated with clinically meaningful measures of benefit (eg, overall survival [OS], quality of life [QoL], or treatment-free interval [TFI]) in a phase 3 clinical trial of an oncolytic virus for melanoma treatment. To evaluate the association between DRR and OS and to mitigate lead time bias, landmark analyses were used. QoL was evaluated using the FACT-BRM questionnaire (comprising the FACT-BRM Physical, Social/Family, Emotional, and Functional well-being domains, the Additional Concerns, Physical and Mental treatment-specific subscales, and the Trial Outcome Index [TOI]). TFI was defined as time from the last study therapy dose to first subsequent therapy dose (including any systemic anticancer therapy for melanoma after study therapy discontinuation). Four hundred thirty-six patients were included in the intent-to-treat population. Achieving DR was associated with a statistically significant improvement in OS in a landmark analysis at 9 months (HR = 0.07; P = 0.0003), 12 months (HR = 0.05, P < 0.0001), and 18 months (HR = 0.11; P = 0.0002) that persisted after adjusting for disease stage and line of therapy. Achieving a DR was associated with a longer median TFI (HR = 0.33; P = 0.0007) and a higher TOI improvement rate (58.1% versus 30.0%; P = 0.025). Achieving a DR was associated with clinical benefits such as improved OS and QoL and prolonged TFI, thus supporting the usefulness of DR as a meaningful immunotherapy clinical trial

  7. Ruxolitinib and Polycation Combination Treatment Overcomes Multiple Mechanisms of Resistance of Pancreatic Cancer Cells to Oncolytic Vesicular Stomatitis Virus.

    Science.gov (United States)

    Felt, Sébastien A; Droby, Gaith N; Grdzelishvili, Valery Z

    2017-08-15

    Vesicular stomatitis virus (VSV) is a promising oncolytic virus (OV). Although VSV is effective against a majority of pancreatic ductal adenocarcinoma cell (PDAC) cell lines, some PDAC cell lines are highly resistant to VSV, and the mechanisms of resistance are still unclear. JAK1/2 inhibitors (such as ruxolitinib and JAK inhibitor I) strongly stimulate VSV replication and oncolysis in all resistant cell lines but only partially improve the susceptibility of resistant PDACs to VSV. VSV tumor tropism is generally dependent on the permissiveness of malignant cells to viral replication rather than on receptor specificity, with several ubiquitously expressed cell surface molecules playing a role in VSV attachment to host cells. However, as VSV attachment to PDAC cells has never been tested before, here we examined if it was possibly inhibited in resistant PDAC cells. Our data show a dramatically weaker attachment of VSV to HPAF-II cells, the most resistant human PDAC cell line. Although sequence analysis of low-density lipoprotein (LDL) receptor (LDLR) mRNA did not reveal any amino acid substitutions in this cell line, HPAF-II cells displayed the lowest level of LDLR expression and dramatically lower LDL uptake. Treatment of cells with various statins strongly increased LDLR expression levels but did not improve VSV attachment or LDL uptake in HPAF-II cells. However, LDLR-independent attachment of VSV to HPAF-II cells was dramatically improved by treating cells with Polybrene or DEAE-dextran. Moreover, combining VSV with ruxolitinib and Polybrene or DEAE-dextran successfully broke the resistance of HPAF-II cells to VSV by simultaneously improving VSV attachment and replication.IMPORTANCE Oncolytic virus (OV) therapy is an anticancer approach that uses viruses that selectively infect and kill cancer cells. This study focuses on oncolytic vesicular stomatitis virus (VSV) against pancreatic ductal adenocarcinoma (PDAC) cells. Although VSV is effective against most PDAC

  8. Oral immunization of swine with attenuated Salmonella typhimurium aroA SL3261 expressing a recombinant antigen of Mycoplasma hyopneumoniae (NrdF) primes the immune system for a NrdF specific secretory IgA response in the lungs.

    Science.gov (United States)

    Fagan, P K; Walker, M J; Chin, J; Eamens, G J; Djordjevic, S P

    2001-02-01

    Salmonella typhimurium SL3261 (aroA mutant) expressing a recombinant Mycoplasma hyopneumoniae antigen was used to orally immunize swine against porcine enzootic pneumonia. This construct, designated S. typhimurium aro A SL3261 (pKF1), expressed a recombinant protein containing the carboxy-terminal 11 kDa of a 42 kDa M. hyopneumoniae NrdF ribonucleotide reductase R2 subunit protein. Here we demonstrate that this antigen is present in all seven geographically diverse strains of M. hyopneumoniae tested, and is recognized by the swine immune system after experimental infection with the virulent M. hyopneumoniae Beaufort strain. The immune response of swine orally immunized twice with S. typhimurium SL3261 (pKF1) on day 0 and day 14 was evaluated. Oral immunization with S. typhimurium SL3261 (pKF1) primed the immune system to elicit a significant (P<0.05) secretory IgA response against the 15 kDa NrdF antigen in the respiratory tract of swine, post-challenge, compared to control groups. Blood lymphocytes from swine immunized with S. typhimurium SL3261 (pKF1) proliferated significantly (P<0.05) following stimulation with M. hyopneumoniae whole-cell extracts compared to control groups 14 days post-vaccination. Following challenge with virulent M. hyopneumoniae, swine immunized with S. typhimurium SL3261 (pKF1) showed higher average daily weight gains and reduced lung pathology compared to control groups. Copyright 2001 Crown Copyright.

  9. Priming T-cell responses with recombinant measles vaccine vector in a heterologous prime-boost setting in non-human primates

    NARCIS (Netherlands)

    Bolton, Diane L.; Santra, Sampa; Swett-Tapia, Cindy; Custers, Jerome; Song, Kaimei; Balachandran, Harikrishnan; Mach, Linh; Naim, Hussein; Kozlowski, Pamela A.; Lifton, Michelle; Goudsmit, Jaap; Letvin, Norman; Roederer, Mario; Radošević, Katarina

    2012-01-01

    Licensed live attenuated virus vaccines capable of expressing transgenes from other pathogens have the potential to reduce the number of childhood immunizations by eliciting robust immunity to multiple pathogens simultaneously. Recombinant attenuated measles virus (rMV) derived from the Edmonston

  10. Cell biology of mitotic recombination

    DEFF Research Database (Denmark)

    Lisby, Michael; Rothstein, Rodney

    2015-01-01

    Homologous recombination provides high-fidelity DNA repair throughout all domains of life. Live cell fluorescence microscopy offers the opportunity to image individual recombination events in real time providing insight into the in vivo biochemistry of the involved proteins and DNA molecules as w...

  11. Science to Practice: Monitoring Oncolytic Virus Therapy with Chemical Exchange Saturation Transfer MR Imaging--Wishful Thinking?

    Science.gov (United States)

    Choyke, Peter L

    2015-06-01

    Farrar et al demonstrate that modifying an oncolytic virus (OV) so that it produces excess protein when it infects a cancer cell is a process that can be detected both in vitro and in vivo in infected cancer cells by using chemical exchange saturation transfer (CEST) magnetic resonance (MR) imaging. The effect is at the limits of MR imaging detection (approximately 1%), but experience with functional MR imaging of the brain, with comparably small effects, should give pause to anyone who immediately writes this observation off as an exercise in wishful thinking. OVs are improving in their specificity, virulence, and ability to induce immune responses. Now, they have been modified to express proteins that are detectable with CEST MR imaging early after delivery into a tumor. This is clearly a surprising and hopeful development in the long road of OVs from the laboratory to the clinic.

  12. The effects of radiation on antitumor efficacy of an oncolytic adenovirus vector in the Syrian hamster model.

    Science.gov (United States)

    Young, B A; Spencer, J F; Ying, B; Toth, K; Wold, W S M

    2013-09-01

    We report that radiation enhances the antitumor efficacy of the oncolytic adenovirus vector VRX-007 in Syrian hamster tumors. We used tumor-specific irradiation of subcutaneous tumors and compared treatment options of radiation alone or combined with VRX-007 and cyclophosphamide (CP). Radiation therapy further augmented the VRX-007-mediated inhibition of tumor growth, in both CP-treated and non-CP-treated hamsters, even though radiation did not lead to increased viral replication in tumors when compared with those treated with VRX-007 alone. Moreover, tumor growth inhibition was similar in tumors irradiated either 1 week before or after injection with VRX-007, which suggests that radiation exerts its antitumor effect independently from vector therapy. Thus, our results demonstrate that these two therapies do not have to be provided simultaneously to enhance their combined effectiveness against subcutaneous hamster tumors.

  13. Interview with Robert Coffin, inventor of T-VEC: the first oncolytic immunotherapy approved for the treatment of cancer.

    Science.gov (United States)

    Coffin, Robert

    2016-02-01

    Interviewed by Ellen Clarke, Commissioning Editor, Future Science Group. Robert Coffin is co-founder and CEO of Replimune. Previously he was Founder and CTO of BioVex Inc, a spin out from his research group at University College London in 1999. He was the inventor of all BioVex products including OncoVEXGM-CSF (talimogene laherparepvec; T-VEC; Imlygic) and oversaw all research and clinical development including bringing T-VEC through to two pivotal Phase 3 studies in melanoma and head and neck cancer. BioVex was acquired by Amgen in 2011 where he was VP Global Development until 2013. T-VEC was approved by the FDA for use in advanced melanoma in October 2015, the first oncolytic therapy or gene therapy to be approved in USA. He was awarded a PhD in virology from Imperial College London prior to his move to University College London in 1991.

  14. FDG-PET/CT for Monitoring Response of Melanoma to the Novel Oncolytic Viral Therapy Talimogene Laherparepvec.

    Science.gov (United States)

    Covington, Matthew F; Curiel, Clara N; Lattimore, Lois; Avery, Ryan J; Kuo, Phillip H

    2017-02-01

    61-year-old woman with stage IIIa (T3a N1a M0) left lower leg melanoma with lesions suggestive of in-transit metastases 8 months following wide local excision and femoral nodal dissection. FDG-PET/CT demonstrated 5 FDG-avid in-transit nodal metastases in the distal left leg, confirmed on biopsy. Talimogene laherparepvec (T-VEC) oncolytic immunotherapy consisting of intralesional injections of modified herpes simplex virus-expressing granulocyte-macrophage colony-stimulating factor was completed over 6 months. Subsequent FDG-PET/CT demonstrated reduced or resolved FDG activity in the treated in-transit metastases and a new FDG-avid left thigh in-transit metastasis. FDG-PET/CT can monitor response to T-VEC and potentially other novel viral immunotherapies.

  15. Into the clinic: Talimogene laherparepvec (T-VEC), a first-in-class intratumoral oncolytic viral therapy.

    Science.gov (United States)

    Rehman, Hasan; Silk, Ann W; Kane, Michael P; Kaufman, Howard L

    2016-01-01

    With the recent regulatory approval of Talimogene laherparepvec (T-VEC) for the treatment of advanced of melanoma in the United States, Europe and Australia, oncolytic virus immunotherapy has earned its place in the clinic. However, the adoption of T-VEC by the U.S. oncology community has been slow, and so far has been largely limited to specialized cancer centers. Limiting factors include the intratumoral route of administration, which is unfamiliar to medical oncologists, biosafety concerns related to the use of a live virus in the clinic, and the explosion of other therapeutic strategies now available for the treatment of advanced melanoma. Herein, we review the development of T-VEC, and suggest how it fits into the in the current clinical treatment paradigm, and provide pearls for drug preparation, administration, and monitoring of response to therapy.

  16. Prime-boost using separate oncolytic viruses in combination with checkpoint blockade improves anti-tumour therapy.

    Science.gov (United States)

    Ilett, E; Kottke, T; Thompson, J; Rajani, K; Zaidi, S; Evgin, L; Coffey, M; Ralph, C; Diaz, R; Pandha, H; Harrington, K; Selby, P; Bram, R; Melcher, A; Vile, R

    2017-01-01

    The anti-tumour effects associated with oncolytic virus therapy are mediated significantly through immune-mediated mechanisms, which depend both on the type of virus and the route of delivery. Here, we show that intra-tumoral oncolysis by Reovirus induced the priming of a CD8+, Th1-type anti-tumour response. By contrast, systemically delivered Vesicular Stomatitis Virus expressing a cDNA library of melanoma antigens (VSV-ASMEL) promoted a potent anti-tumour CD4+ Th17 response. Therefore, we hypothesised that combining the Reovirus-induced CD8+ T cell response, with the VSV-ASMEL CD4+ Th17 helper response, would produce enhanced anti-tumour activity. Consistent with this, priming with intra-tumoral Reovirus, followed by an intra-venous VSV-ASMEL Th17 boost, significantly improved survival of mice bearing established subcutaneous B16 melanoma tumours. We also show that combination of either therapy alone with anti-PD-1 immune checkpoint blockade augmented both the Th1 response induced by systemically delivered Reovirus in combination with GM-CSF, and also the Th17 response induced by VSV-ASMEL. Significantly, anti-PD-1 also uncovered an anti-tumour Th1 response following VSV-ASMEL treatment that was not seen in the absence of checkpoint blockade. Finally, the combination of all three treatments (priming with systemically delivered Reovirus, followed by double boosting with systemic VSV-ASMEL and anti-PD-1) significantly enhanced survival, with long-term cures, compared to any individual, or double, combination therapies, associated with strong Th1 and Th17 responses to tumour antigens. Our data show that it is possible to generate fully systemic, highly effective anti-tumour immunovirotherapy by combining oncolytic viruses, along with immune checkpoint blockade, to induce complementary mechanisms of anti-tumour immune responses.

  17. Treatment of medulloblastoma using an oncolytic measles virus encoding the thyroidal sodium iodide symporter shows enhanced efficacy with radioiodine

    Directory of Open Access Journals (Sweden)

    Hutzen Brian

    2012-11-01

    Full Text Available Abstract Background Medulloblastoma is the most common malignant brain tumor of childhood. Although the clinical outcome for medulloblastoma patients has improved significantly, children afflicted with the disease frequently suffer from debilitating side effects related to the aggressive nature of currently available therapy. Alternative means for treating medulloblastoma are desperately needed. We have previously shown that oncolytic measles virus (MV can selectively target and destroy medulloblastoma tumor cells in localized and disseminated models of the disease. MV-NIS, an oncolytic measles virus that encodes the human thyroidal sodium iodide symporter (NIS, has the potential to deliver targeted radiotherapy to the tumor site and promote a localized bystander effect above and beyond that achieved by MV alone. Methods We evaluated the efficacy of MV-NIS against medulloblastoma cells in vitro and examined their ability to incorporate radioiodine at various timepoints, finding peak uptake at 48 hours post infection. The effects of MV-NIS were also evaluated in mouse xenograft models of localized and disseminated medulloblastoma. Athymic nude mice were injected with D283med-Luc medulloblastoma cells in the caudate putamen (localized disease or right lateral ventricle (disseminated disease and subsequently treated with MV-NIS. Subsets of these mice were given a dose of 131I at 24, 48 or 72 hours later. Results MV-NIS treatment, both by itself and in combination with 131I, elicited tumor stabilization and regression in the treated mice and significantly extended their survival times. Mice given 131I were found to concentrate radioiodine at the site of their tumor implantations. In addition, mice with localized tumors that were given 131I either 24 or 48 hours after MV-NIS treatment exhibited a significant survival advantage over mice given MV-NIS alone. Conclusions These data suggest MV-NIS plus radioiodine may be a potentially useful therapy for

  18. Oncolytic gene therapy combined with double suicide genes for human bile duct cancer in nude mouse models.

    Science.gov (United States)

    Kojima, Yoh; Honda, Kazuo; Hamada, Hirofumi; Kobayashi, Nobuaki

    2009-11-01

    The prognosis of bile duct cancer is quite poor because of the low resection rate and the tolerance of the cancer to chemotherapy and radiotherapy. We investigated the feasibility of an oncolytic adenovector with two suicide genes for the treatment of bile duct cancer. We developed a new conditionally replicating adenovirus (AxE1CAUT) with the uracil phosphoribosyltransferase (UPRT) gene and the herpes simplex virus thymidine kinase (HSV-tk) gene, and compared its antitumor effects with a replication defective adenovector (AxCAUT) that has both the UPRT and HSV-tk genes. We evaluated the effects of these adenoviruses with 5-fluorouracil (5-FU) and/or ganciclovir (GCV) on human cholangiocarcinoma cells (HuCCT1, with mutant p53) in vitro and in vivo. The drug sensitivity of HuCCT1 cells to 5-FU and/or GCV was increased with an increase in the multiplicity of infection (MOI). The antitumor effect increased when 5-FU and GCV were given at the same time. Subcutaneous tumors of nude mice directly injected with AxCAUT showed a higher response to 5-FU/GCV than 5-FU or GCV alone, but there was no difference between AxCAUT and AxE1CAUT. However, AxE1CAUT with 5-FU/GCV produced a decrease in tumor weight and better survival than AxCAUT in a peritoneal dissemination model infected by intraperitoneal administration of the adenovectors. Oncolytic double suicide gene therapy is effective against human cholangiocarcinoma cells in nude mouse models.

  19. Oncolytic viruses sensitize human tumor cells for NY-ESO-1 tumor antigen recognition by CD4+ effector T cells.

    Science.gov (United States)

    Delaunay, Tiphaine; Violland, Mathilde; Boisgerault, Nicolas; Dutoit, Soizic; Vignard, Virginie; Münz, Christian; Gannage, Monique; Dréno, Brigitte; Vaivode, Kristine; Pjanova, Dace; Labarrière, Nathalie; Wang, Yaohe; Chiocca, E Antonio; Boeuf, Fabrice Le; Bell, John C; Erbs, Philippe; Tangy, Frédéric; Grégoire, Marc; Fonteneau, Jean-François

    2018-01-01

    Oncolytic immunotherapy using oncolytic viruses (OV) has been shown to stimulate the antitumor immune response by inducing the release of tumor-associated antigens (TAA) and danger signals from the dying infected tumor cells. In this study, we sought to determine if the lysis of tumor cells induced by different OV: measles virus, vaccinia virus, vesicular stomatitis virus, herpes simplex type I virus, adenovirus or enterovirus, has consequences on the capacity of tumor cells to present TAA, such as NY-ESO-1. We show that the co-culture of NY-ESO-1 neg /HLA-DP4 pos melanoma cells with NY-ESO-1 pos /HLA-DP4 neg melanoma cells infected and killed by different OV induces an intercellular transfer of NY-ESO-1 that allows the recognition of NY-ESO-1 neg /HLA-DP4 pos tumor cells by an HLA-DP4/NY-ESO-1 (157-170) -specific CD4+ cytotoxic T cell clone, NY67. We then confirmed this result in a second model with an HLA-DP4+ melanoma cell line that expresses a low amount of NY-ESO-1. Recognition of this cell line by the NY67 clone is largely increased in the presence of OV productive infection. Altogether, our results show for the first time another mechanism of stimulation of the anti-tumor immune response by OV, via the loading of tumor cells with TAA that sensitizes them for direct recognition by specific effector CD4+ T cells, supporting the use of OV for cancer immunotherapy.

  20. Oncolytic effects of parvovirus H-1 in medulloblastoma are associated with repression of master regulators of early neurogenesis

    Science.gov (United States)

    Lacroix, Jeannine; Schlund, Franziska; Leuchs, Barbara; Adolph, Kathrin; Sturm, Dominik; Bender, Sebastian; Hielscher, Thomas; Pfister, Stefan M; Witt, Olaf; Rommelaere, Jean; Schlehofer, Jörg R; Witt, Hendrik

    2014-01-01

    Based on extensive pre-clinical studies, the oncolytic parvovirus H-1 (H-1PV) is currently applied to patients with recurrent glioblastoma in a phase I/IIa clinical trial (ParvOryx01, NCT01301430). Cure rates of about 40% in pediatric high-risk medulloblastoma (MB) patients also indicate the need of new therapeutic approaches. In order to prepare a future application of oncolytic parvovirotherapy to MB, the present study preclinically evaluates the cytotoxic efficacy of H-1PV on MB cells in vitro and characterizes cellular target genes involved in this effect. Six MB cell lines were analyzed by whole genome oligonucleotide microarrays after treatment and the results were matched to known molecular and cytogenetic risk factors. In contrast to non-transformed infant astrocytes and neurons, in five out of six MB cell lines lytic H-1PV infection and efficient viral replication could be demonstrated. The cytotoxic effects induced by H-1PV were observed at LD50s below 0.05 p. f. u. per cell indicating high susceptibility. Gene expression patterns in the responsive MB cell lines allowed the identification of candidate target genes mediating the cytotoxic effects of H-1PV. H-1PV induced down-regulation of key regulators of early neurogenesis shown to confer poor prognosis in MB such as ZIC1, FOXG1B, MYC, and NFIA. In MB cell lines with genomic amplification of MYC, expression of MYC was the single gene most significantly repressed after H-1PV infection. H-1PV virotherapy may be a promising treatment approach for MB since it targets genes of functional relevance and induces cell death at very low titers of input virus. PMID:23852775

  1. Therapeutic efficacy of an oncolytic adenovirus containing RGD ligand in minor capsid protein IX and Fiber, Δ24DoubleRGD, in an ovarian cancer model

    Directory of Open Access Journals (Sweden)

    Anton V Borovjagin

    2012-02-01

    Full Text Available Ovarian cancer is the leading cause of gynecological disease death despite advances in medicine. Therefore, novel strategies are required for ovarian cancer therapy. Conditionally replicative adenoviruses (CRAds, genetically modified as anti-cancer therapeutics, are one of the most attractive candidate agents for cancer therapy. However, a paucity of coxsackie B virus and adenovirus receptor (CAR expression on the surface of ovarian cancer cells has impeded treatment of ovarian cancer using this approach.This study sought to engineer a CRAd with enhanced oncolytic ability in ovarian cancer cells, “Δ24DoubleRGD.” Δ24DoubleRGD carries an arginine-glycine-aspartate (RGD motif incorporated into both fiber and capsid protein IX (pIX and its oncolytic efficacy was evaluated in ovarian cancer. In vitro analysis of cell viability showed that infection of ovarian cancer cells with Δ24DoubleRGD leads to increased cell killing relative to the control CRAds. Data from this study suggested that not only an increase in number of RGD motifs on the CRAd capsid, but also a change in the repertoir of targeted integrins could lead to enhanced oncolytic potency of Δ24DoubleRGD in ovarian cancer cells in vitro. In an intraperitoneal model of ovarian cancer, mice injected with Δ24DoubleRGD showed, however, a similar survival rate as mice treated with control CRAds.

  2. Pharmacokinetic study of neural stem cell-based cell carrier for oncolytic virotherapy: targeted delivery of the therapeutic payload in an orthotopic brain tumor model.

    Science.gov (United States)

    Thaci, B; Ahmed, A U; Ulasov, I V; Tobias, A L; Han, Y; Aboody, K S; Lesniak, M S

    2012-06-01

    Oncolytic virotherapy is a promising novel therapy for glioblastoma that needs to be optimized before introduced to clinic. The targeting of conditionally replicating adenoviruses (CRAds) can be improved by relying on the tumor-tropic properties of neural stem cells (NSCs). Here, we report the characterization of an FDA approved NSC, HB1.F3-CD, as a cell carrier for CRAd-S-pk7, a glioma-tropic oncolytic adenovirus. We show that NSCs replicate and release infectious CRAd-S-pk7 progeny capable of lysing glioma cell lines. Moreover, ex-vivo-loaded NSCs, injected intracranially in nude mice bearing human glioma xenografts (i) retained their tumor tropism, (ii) continued to replicate CRAd-S-pk7 for more than a week after reaching the tumor site and (iii) successfully handed off CRAd-S-pk7 to glioma cells in vivo. Delivery via carrier cells reduced non-specific adenovirus distribution in the mouse brain. Moreover, we assessed biodistribution of loaded NSCs after intracranial injection in animal models semi-permissive to adenovirus replication, the Syrian hamster and cotton rat. NSCs did not migrate to distant organs and high levels of CRAd-S-pk7 DNA were observed only in the injected hemisphere. In conclusion, this optimized carrier system, with high efficiency of adenovirus delivery and minimal systemic toxicity, poses considerable advantages for anti-glioma oncolytic virotherapy.

  3. Oncolytic Herpes Virus rRp450 Shows Efficacy in Orthotopic Xenograft Group 3/4 Medulloblastomas and Atypical Teratoid/Rhabdoid Tumors

    Directory of Open Access Journals (Sweden)

    Adam W. Studebaker

    2017-09-01

    Full Text Available Pediatric brain tumors including medulloblastoma and atypical teratoid/rhabdoid tumor are associated with significant mortality and treatment-associated morbidity. While medulloblastoma tumors within molecular subgroups 3 and 4 have a propensity to metastasize, atypical teratoid/rhabdoid tumors frequently afflict a very young patient population. Adjuvant treatment options for children suffering with these tumors are not only sub-optimal but also associated with many neurocognitive obstacles. A potentially novel treatment approach is oncolytic virotherapy, a developing therapeutic platform currently in early-phase clinical trials for pediatric brain tumors and recently US Food and Drug Administration (FDA-approved to treat melanoma in adults. We evaluated the therapeutic potential of the clinically available oncolytic herpes simplex vector rRp450 in cell lines derived from medulloblastoma and atypical teratoid/rhabdoid tumor. Cells of both tumor types were supportive of virus replication and virus-mediated cytotoxicity. Orthotopic xenograft models of medulloblastoma and atypical teratoid/rhabdoid tumors displayed significantly prolonged survival following a single, stereotactic intratumoral injection of rRp450. Furthermore, addition of the chemotherapeutic prodrug cyclophosphamide (CPA enhanced rRp450’s in vivo efficacy. In conclusion, oncolytic herpes viruses with the ability to bioactivate the prodrug CPA within the tumor microenvironment warrant further investigation as a potential therapy for pediatric brain tumors.

  4. Pancreatic adenocarcinoma upregulated factor (PAUF) confers resistance to pancreatic cancer cells against oncolytic parvovirus H-1 infection through IFNA receptor-mediated signaling

    Energy Technology Data Exchange (ETDEWEB)

    Kaowinn, Sirichat; Cho, Il-Rae; Moon, Jeong; Jun, Seung Won; Kim, Chang Seok [BK21+, Department of Cogno-Mechatronics Engineering, Pusan National University, Busan 609-736 (Korea, Republic of); Kang, Ho Young [Department of Microbiology, Pusan National University, Busan 609-736 (Korea, Republic of); Kim, Manbok [Department of Medical Science, Dankook University College of Medicine, Cheonan 330-714 (Korea, Republic of); Koh, Sang Seok [Department of Biological Sciences, Dong-A University, Busan 604-714 (Korea, Republic of); Chung, Young-Hwa, E-mail: younghc@pusan.ac.kr [BK21+, Department of Cogno-Mechatronics Engineering, Pusan National University, Busan 609-736 (Korea, Republic of)

    2015-04-03

    Pancreatic adenocarcinoma upregulated factor (PAUF), a novel oncogene, plays a crucial role in the development of pancreatic cancer, including its metastasis and proliferation. Therefore, PAUF-expressing pancreatic cancer cells could be important targets for oncolytic virus-mediated treatment. Panc-1 cells expressing PAUF (Panc-PAUF) showed relative resistance to parvovirus H-1 infection compared with Panc-1 cells expressing an empty vector (Panc-Vec). Of interest, expression of type I IFN-α receptor (IFNAR) was higher in Panc-PAUF cells than in Panc-Vec cells. Increased expression of IFNAR in turn increased the activation of Stat1 and Tyk2 in Panc-PAUF cells compared with that in Panc-Vec cells. Suppression of Tyk2 and Stat1, which are important downstream molecules for IFN-α signaling, sensitized pancreatic cancer cells to parvovirus H-1-mediated apoptosis. Further, constitutive suppression of PAUF sensitized Bxpc3 pancreatic cancer cells to parvovirus H-1 infection. Taken together, these results suggested that PAUF conferred resistance to pancreatic cancer cells against oncolytic parvovirus H-1 infection through IFNAR-mediated signaling. - Highlights: • PAUF confers resistance against oncolytic parvovirus H-1 infection. • PAUF enhances the expression of IFNAR in Panc-1 cells. • Increased activation of Tyk2 or Stat1 by PAUF provides resistance to parvovirus H-1-mediated apoptosis. • Constitutive inhibition of PAUF enhances parvovirus H-1-mediated oncolysis of Bxpc3 pancreatic cancer cells.

  5. CD47-retargeted oncolytic adenovirus armed with melanoma differentiation-associated gene-7/interleukin-24 suppresses in vivo leukemia cell growth.

    Science.gov (United States)

    Li, Gongchu; Wu, Hu; Cui, Lianzhen; Gao, Yajun; Chen, Lei; Li, Xin; Liang, Tianxiang; Yang, Xinyan; Cheng, Jianhong; Luo, Jingjing

    2015-12-22

    Our previous studies have suggested that harboring a soluble coxsackie-adenovirus receptor-ligand (sCAR-ligand) fusion protein expression cassette in the viral genome may provide a universal method to redirect oncolytic adenoviruses to various membrane receptors on cancer cells resisting to serotype 5 adenovirus infection. We report here a novel oncolytic adenovirus vector redirected to CD47+ leukemia cells though carrying a sCAR-4N1 expression cassette in the viral genome, forming Ad.4N1, in which 4N1 represents the C-terminal CD47-binding domain of thrombospondin-1. The infection and cytotoxicity of Ad.4N1 in leukemia cells were determined to be mediated by the 4N1-CD47 interaction. Ad.4N1 was further engineered to harbor a gene encoding melanoma differentiation-associated gene-7/interleukin-24 (mda-7/IL-24), forming Ad.4N1-IL24, which replicated dramatically faster than Ad.4N1, and elicited significantly enhanced antileukemia effect in vitro and in a HL60/Luc xenograft mouse model. Our data suggest that Ad.4N1 could act as a novel oncolytic adenovirus vector for CD47+ leukemia targeting gene transfer, and Ad.4N1 harboring anticancer genes may provide novel antileukemia agents.

  6. Vaccinia virus outperforms a panel of other poxviruses as a potent oncolytic agent for the control of head and neck squamous cell carcinoma cell lines.

    Science.gov (United States)

    Nichols, Anthony C; Yoo, John; Um, Sung; Mundi, Neil; Palma, David A; Fung, Kevin; Macneil, S Danielle; Koropatnick, James; Mymryk, Joe S; Barrett, John W

    2014-01-01

    Head and neck squamous cell carcinoma (HNSCC) is the fifth most common cancer worldwide. Existing therapies for advanced tumors have high failure rates and can have severe consequences in terms of pain, disfigurement, and poor speech and swallowing function. New treatment strategies are needed to improve outcomes for patients suffering with this disease and oncolytic viruses represent a promising approach. We infected six well-characterized HNSCC cell lines (Cal27, Detroit562, FaDu, SCC4, SCC15, SCC25), with increasing doses of a panel of poxviruses (including myxoma, vaccinia, raccoonpox and tanapox viruses) modified to express green fluorescence protein to determine which virus was the most effective oncolytic agent in cell-based assays. While myxoma, raccoonpox and tanapox displayed differing efficacy in the panel of cell lines, vaccinia virus was the most potent of the tested poxviruses and was highly effective in controlling cell growth in all cell lines. Oncolytic poxviruses, particularly vaccinia virus, were effective in killing HNSCC in vitro and hold promise as potential treatments for patients with HNSCC. Copyright © 2013 S. Karger AG, Basel.

  7. Controlled release from recombinant polymers.

    Science.gov (United States)

    Price, Robert; Poursaid, Azadeh; Ghandehari, Hamidreza

    2014-09-28

    Recombinant polymers provide a high degree of molecular definition for correlating structure with function in controlled release. The wide array of amino acids available as building blocks for these materials lend many advantages including biorecognition, biodegradability, potential biocompatibility, and control over mechanical properties among other attributes. Genetic engineering and DNA manipulation techniques enable the optimization of structure for precise control over spatial and temporal release. Unlike the majority of chemical synthetic strategies used, recombinant DNA technology has allowed for the production of monodisperse polymers with specifically defined sequences. Several classes of recombinant polymers have been used for controlled drug delivery. These include, but are not limited to, elastin-like, silk-like, and silk-elastinlike proteins, as well as emerging cationic polymers for gene delivery. In this article, progress and prospects of recombinant polymers used in controlled release will be reviewed. Copyright © 2014 Elsevier B.V. All rights reserved.

  8. Three Decades of Recombinant DNA.

    Science.gov (United States)

    Palmer, Jackie

    1985-01-01

    Discusses highlights in the development of genetic engineering, examining techniques with recombinant DNA, legal and ethical issues, GenBank (a national database of nucleic acid sequences), and other topics. (JN)

  9. Controlled Release from Recombinant Polymers

    Science.gov (United States)

    Price, Robert; Poursaid, Azadeh; Ghandehari, Hamidreza

    2014-01-01

    Recombinant polymers provide a high degree of molecular definition for correlating structure with function in controlled release. The wide array of amino acids available as building blocks for these materials lend many advantages including biorecognition, biodegradability, potential biocompatibility, and control over mechanical properties among other attributes. Genetic engineering and DNA manipulation techniques enable the optimization of structure for precise control over spatial and temporal release. Unlike the majority of chemical synthetic strategies used, recombinant DNA technology has allowed for the production of monodisperse polymers with specifically defined sequences. Several classes of recombinant polymers have been used for controlled drug delivery. These include, but are not limited to, elastin-like, silk-like, and silk-elastinlike proteins, as well as emerging cationic polymers for gene delivery. In this article, progress and prospects of recombinant polymers used in controlled release will be reviewed. PMID:24956486

  10. Horizontal transmissible protection against myxomatosis and rabbit hemorrhagic disease by using a recombinant myxoma virus.

    Science.gov (United States)

    Bárcena, J; Morales, M; Vázquez, B; Boga, J A; Parra, F; Lucientes, J; Pagès-Manté, A; Sánchez-Vizcaíno, J M; Blasco, R; Torres, J M

    2000-02-01

    We have developed a new strategy for immunization of wild rabbit populations against myxomatosis and rabbit hemorrhagic disease (RHD) that uses recombinant viruses based on a naturally attenuated field strain of myxoma virus (MV). The recombinant viruses expressed the RHDV major capsid protein (VP60) including a linear epitope tag from the transmissible gastroenteritis virus (TGEV) nucleoprotein. Following inoculation, the recombinant viruses induced specific antibody responses against MV, RHDV, and the TGEV tag. Immunization of wild rabbits by the subcutaneous and oral routes conferred protection against virulent RHDV and MV challenges. The recombinant viruses showed a limited horizontal transmission capacity, either by direct contact or in a flea-mediated process, promoting immunization of contact uninoculated animals.

  11. Recombinant snake venom prothrombin activators

    OpenAIRE

    L?vgren, Ann

    2012-01-01

    Three prothrombin activators; ecarin, which was originally isolated from the venom of the saw-scaled viper Echis carinatus, trocarin from the rough-scaled snake Tropidechis carinatus, and oscutarin from the Taipan snake Oxyuranus scutellatus, were expressed in mammalian cells with the purpose to obtain recombinant prothrombin activators that could be used to convert prothrombin to thrombin. We have previously reported that recombinant ecarin can efficiently generate thrombin without the need ...

  12. Heterogeneity in recombinant protein production

    DEFF Research Database (Denmark)

    Schalén, Martin; Johanson, Ted; Lundin, Luisa

    2012-01-01

    contribute to make a population in a fermenter heterogeneous, resulting in cell-to-cell variation in physiological parameters of the microbial culture. Our study aims at investigating how population heterogeneity and recombinant protein production is affected by environmental gradients in bioreactors...... are simulated in small bioreactors and the population heterogeneity can be visualised by analysing single cells with flow cytometry. This can give new insights to cell physiology and recombinant protein production at the industrial scale....

  13. Oncolytic targeting of androgen-sensitive prostate tumor by the respiratory syncytial virus (RSV: consequences of deficient interferon-dependent antiviral defense

    Directory of Open Access Journals (Sweden)

    Hubbard Gene B

    2011-01-01

    Full Text Available Abstract Background Oncolytic virotherapy for cancer treatment utilizes viruses for selective infection and death of cancer cells without any adverse effect on normal cells. We previously reported that the human respiratory syncytial virus (RSV is a novel oncolytic virus against androgen-independent PC-3 human prostate cancer cells. The present study extends the result to androgen-dependent prostate cancer, and explores the underlying mechanism that triggers RSV-induced oncolysis of prostate cancer cells. Methods The oncolytic effect of RSV on androgen-sensitive LNCaP human prostate cancer cells and on androgen-independent RM1 murine prostate cancer cells was studied in vitro in culture and in vivo in a xenograft or allograft tumor model. In vitro, cell viability, infectivity and apoptosis were monitored by MTT assay, viral plaque assay and annexin V staining, respectively. In vivo studies involved virus administration to prostate tumors grown in immune compromised nude mice and in syngeneic immune competent C57BL/6J mice. Anti-tumorogenic oncolytic activity was monitored by measuring tumor volume, imaging bioluminescent tumors in live animals and performing histopathological analysis and TUNEL assay with tumors Results We show that RSV imposes a potent oncolytic effect on LNCaP prostate cancer cells. RSV infectivity was markedly higher in LNCaP cells compared to the non-tumorigenic RWPE-1 human prostate cells. The enhanced viral burden led to LNCaP cell apoptosis and growth inhibition of LNCaP xenograft tumors in nude mice. A functional host immune response did not interfere with RSV-induced oncolysis, since growth of xenograft tumors in syngeneic C57BL/6J mice from murine RM1 cells was inhibited upon RSV administration. LNCaP cells failed to activate the type-I interferon (IFNα/β-induced transcription factor STAT-1, which is required for antiviral gene expression, although these cells could produce IFN in response to RSV infection. The

  14. RECOMBINANT HORSERADISH PEROXIDASE FOR ANALYTICAL APPLICATIONS

    Directory of Open Access Journals (Sweden)

    А.M. Egorov

    2012-08-01

    Full Text Available The article deals with prospects of using recombinant horseradish peroxidase in analytical biochemistry and biotechnology. Problems of recombinant horseradish peroxidase cloning in different expression systems, possible approaches to their solution, advantages of recombinant recombinant horseradish peroxidase and recombinant horseradish peroxidase-fusion proteins for immunoassays are considered. Possibility for development of mediatorless bienzyme biosensor for peroxide and metabolites, yielding hydrogen peroxide during their transformations, based on co-adsorption of recombinant horseradish peroxidase and the appropriate oxidase was demonstrated. The possibility to produce a fully active recombinant conjugate of recombinant horseradish peroxidase with human heart-type fatty acid binding protein, which may be used in competitive immunoassay for clinical diagnosis of acute myocardial infarction, and recombinant conjugates (N- and C-terminus of recombinant horseradish peroxidase with Fab-fragments of the antibody against atrazine, which may be applied for atrazine pesticides detection, are demonstra ted for the first time.

  15. Recombination drives vertebrate genome contraction.

    Science.gov (United States)

    Nam, Kiwoong; Ellegren, Hans

    2012-01-01

    Selective and/or neutral processes may govern variation in DNA content and, ultimately, genome size. The observation in several organisms of a negative correlation between recombination rate and intron size could be compatible with a neutral model in which recombination is mutagenic for length changes. We used whole-genome data on small insertions and deletions within transposable elements from chicken and zebra finch to demonstrate clear links between recombination rate and a number of attributes of reduced DNA content. Recombination rate was negatively correlated with the length of introns, transposable elements, and intergenic spacer and with the rate of short insertions. Importantly, it was positively correlated with gene density, the rate of short deletions, the deletion bias, and the net change in sequence length. All these observations point at a pattern of more condensed genome structure in regions of high recombination. Based on the observed rates of small insertions and deletions and assuming that these rates are representative for the whole genome, we estimate that the genome of the most recent common ancestor of birds and lizards has lost nearly 20% of its DNA content up until the present. Expansion of transposable elements can counteract the effect of deletions in an equilibrium mutation model; however, since the activity of transposable elements has been low in the avian lineage, the deletion bias is likely to have had a significant effect on genome size evolution in dinosaurs and birds, contributing to the maintenance of a small genome. We also demonstrate that most of the observed correlations between recombination rate and genome contraction parameters are seen in the human genome, including for segregating indel polymorphisms. Our data are compatible with a neutral model in which recombination drives vertebrate genome size evolution and gives no direct support for a role of natural selection in this process.

  16. Safety evaluation of a recombinant myxoma-RHDV virus inducing horizontal transmissible protection against myxomatosis and rabbit haemorrhagic disease.

    Science.gov (United States)

    Torres, J M; Ramírez, M A; Morales, M; Bárcena, J; Vázquez, B; Espuña, E; Pagès-Manté, A; Sánchez-Vizcaíno, J M

    2000-09-15

    We have recently developed a transmissible vaccine to immunize rabbits against myxomatosis and rabbit haemorrhagic disease based on a recombinant myxoma virus (MV) expressing the rabbit haemorrhagic disease virus (RHDV) capsid protein [Bárcena et al. Horizontal transmissible protection against myxomatosis and rabbit haemorragic disease using a recombinant myxoma virus. J. Virol. 2000;74:1114-23]. Administration of the recombinant virus protects rabbits against lethal RHDV and MV challenges. Furthermore, the recombinant virus is capable of horizontal spreading promoting protection of contact animals, thus providing the opportunity to immunize wild rabbit populations. However, potential risks must be extensively evaluated before considering its field use. In this study several safety issues concerning the proposed vaccine have been evaluated under laboratory conditions. Results indicated that vaccine administration is safe even at a 100-fold overdose. No undesirable effects were detected upon administration to immunosuppressed or pregnant rabbits. The recombinant virus maintained its attenuated phenotype after 10 passages in vivo.

  17. [Rapid selection of recombinant orf virus expression vectors using green fluorescent protein].

    Science.gov (United States)

    Zhang, Jiachun; Guo, Xianfeng; Zhang, Min; Wu, Feifan; Peng, Yongzheng

    2016-01-01

    To construct a universal, highly attenuated orf virus expression vector for exogenous genes using green fluorescent protein (GFP) as the reporter gene. The flanking regions of the ORFV132 of orf virus DNA were amplified by PCR to construct the shuttle plasmid pSPV-132LF-EGFP-132RF. The shuttle plasmid was transfected into OFTu cells and GFP was incorporated into orf virus IA82Delta 121 by homologous recombination. The recombinant IA82Delta121-V was selected by green fluorescent signal. The deletion gene was identified by PCR and sequencing. The effects of ORFV132 knockout were evaluated by virus titration and by observing the proliferation of the infected vascular endothelial cells in vitro. The recombinant orf virus IA82Delta121-V was obtained successfully and quickly, and the deletion of ORFV132 did not affect the replication of the virus in vitro but reduced its virulence. Green fluorescent protein is a selectable marker for rapid, convenient and stable selection of the recombinant viruses. Highly attenuated recombinant orf virus IA82Delta121-V can serve as a new expression vector for exogenous genes.

  18. Imaging characteristics, tissue distribution, and spread of a novel oncolytic vaccinia virus carrying the human sodium iodide symporter.

    Directory of Open Access Journals (Sweden)

    Dana Haddad

    Full Text Available INTRODUCTION: Oncolytic viruses show promise for treating cancer. However, to assess therapy and potential toxicity, a noninvasive imaging modality is needed. This study aims to determine the in vivo biodistribution, and imaging and timing characteristics of a vaccinia virus, GLV-1h153, encoding the human sodium iodide symporter (hNIS. METHODS: GLV-1h153 was modified from GLV-1h68 to encode the hNIS gene. Timing of cellular uptake of radioiodide (131I in human pancreatic carcinoma cells PANC-1 was assessed using radiouptake assays. Viral biodistribution was determined in nude mice bearing PANC-1 xenografts, and infection in tumors confirmed histologically and optically via Green Fluorescent Protein (GFP and bioluminescence. Timing characteristics of enhanced radiouptake in xenografts were assessed via (124I-positron emission tomography (PET. Detection of systemic administration of virus was investigated with both (124I-PET and 99m-technecium gamma-scintigraphy. RESULTS: GLV-1h153 successfully facilitated time-dependent intracellular uptake of (131I in PANC-1 cells with a maximum uptake at 24 hours postinfection (P<0.05. In vivo, biodistribution profiles revealed persistence of virus in tumors 5 weeks postinjection at 10(9 plaque-forming unit (PFU/gm tissue, with the virus mainly cleared from all other major organs. Tumor infection by GLV-1h153 was confirmed via optical imaging and histology. GLV-1h153 facilitated imaging virus replication in tumors via PET even at 8 hours post radiotracer injection, with a mean %ID/gm of 3.82 ± 0.46 (P<0.05 2 days after intratumoral administration of virus, confirmed via tissue radiouptake assays. One week post systemic administration, GLV-1h153-infected tumors were detected via (124I-PET and 99m-technecium-scintigraphy. CONCLUSION: GLV-1h153 is a promising oncolytic agent against pancreatic cancer with a promising biosafety profile. GLV-1h153 facilitated time-dependent hNIS-specific radiouptake in pancreatic

  19. Synergistic antitumor activity of oncolytic reovirus and chemotherapeutic agents in non-small cell lung cancer cells

    Directory of Open Access Journals (Sweden)

    Coffey Matthew C

    2009-07-01

    Full Text Available Abstract Background Reovirus type 3 Dearing strain (ReoT3D has an inherent propensity to preferentially infect and destroy cancer cells. The oncolytic activity of ReoT3D as a single agent has been demonstrated in vitro and in vivo against various cancers, including colon, pancreatic, ovarian and breast cancers. Its human safety and potential efficacy are currently being investigated in early clinical trials. In this study, we investigated the in vitro combination effects of ReoT3D and chemotherapeutic agents against human non-small cell lung cancer (NSCLC. Results ReoT3D alone exerted significant cytolytic activity in 7 of 9 NSCLC cell lines examined, with the 50% effective dose, defined as the initial virus dose to achieve 50% cell killing after 48 hours of infection, ranging from 1.46 ± 0.12 ~2.68 ± 0.25 (mean ± SD log10 pfu/cell. Chou-Talalay analysis of the combination of ReoT3D with cisplatin, gemcitabine, or vinblastine demonstrated strong synergistic effects on cell killing, but only in cell lines that were sensitive to these compounds. In contrast, the combination of ReoT3D and paclitaxel was invariably synergistic in all cell lines tested, regardless of their levels of sensitivity to either agent. Treatment of NSCLC cell lines with the ReoT3D-paclitaxel combination resulted in increased poly (ADP-ribose polymerase cleavage and caspase activity compared to single therapy, indicating enhanced apoptosis induction in dually treated NSCLC cells. NSCLC cells treated with the ReoT3D-paclitaxel combination showed increased proportions of mitotic and apoptotic cells, and a more pronounced level of caspase-3 activation was demonstrated in mitotically arrested cells. Conclusion These data suggest that the oncolytic activity of ReoT3D can be potentiated by taxanes and other chemotherapeutic agents, and that the ReoT3D-taxane combination most effectively achieves synergy through accelerated apoptosis triggered by prolonged mitotic arrest.

  20. Genomic Signature of the Natural Oncolytic Herpes Simplex Virus HF10 and Its Therapeutic Role in Preclinical and Clinical Trials.

    Science.gov (United States)

    Eissa, Ibrahim Ragab; Naoe, Yoshinori; Bustos-Villalobos, Itzel; Ichinose, Toru; Tanaka, Maki; Zhiwen, Wu; Mukoyama, Nobuaki; Morimoto, Taishi; Miyajima, Noriyuki; Hitoki, Hasegawa; Sumigama, Seiji; Aleksic, Branko; Kodera, Yasuhiro; Kasuya, Hideki

    2017-01-01

    Oncolytic viruses (OVs) are opening new possibilities in cancer therapy with their unique mechanism of selective replication within tumor cells and triggering of antitumor immune responses. HF10 is an oncolytic herpes simplex virus-1 with a unique genomic structure that has non-engineered deletions and insertions accompanied by frame-shift mutations, in contrast to the majority of engineered OVs. At the genetic level, HF10 naturally lacks the expression of UL43, UL49.5, UL55, UL56, and latency-associated transcripts, and overexpresses UL53 and UL54. In preclinical studies, HF10 replicated efficiently within tumor cells with extensive cytolytic effects and induced increased numbers of activated CD4(+) and CD8(+) T cells and natural killer cells within the tumor, leading to a significant reduction in tumor growth and prolonged survival rates. Investigator-initiated clinical studies of HF10 have been completed in recurrent breast carcinoma, head and neck cancer, and unresectable pancreatic cancer in Japan. Phase I trials were subsequently completed in refractory superficial cancers and melanoma in the United States. HF10 has been demonstrated to have a high safety margin with low frequency of adverse effects in all treated patients. Interestingly, HF10 antigens were detected in pancreatic carcinoma over 300 days after treatment with infiltration of CD4(+) and CD8(+) T cells, which enhanced the immune response. To date, preliminary results from a Phase II trial have indicated that HF10 in combination with ipilimumab (anti-CTLA-4) is safe and well tolerated, with high antitumor efficacy. Improvement of the effect of ipilimumab was observed in patients with stage IIIb, IIIc, or IV unresectable or metastatic melanoma. This review provides a concise description of the genomic functional organization of HF10 compared with talimogene laherparepvec. Furthermore, this review focuses on HF10 in cancer treatment as monotherapy as well as in combination therapy through a

  1. Genomic Signature of the Natural Oncolytic Herpes Simplex Virus HF10 and Its Therapeutic Role in Preclinical and Clinical Trials

    Directory of Open Access Journals (Sweden)

    Ibrahim Ragab Eissa

    2017-07-01

    Full Text Available Oncolytic viruses (OVs are opening new possibilities in cancer therapy with their unique mechanism of selective replication within tumor cells and triggering of antitumor immune responses. HF10 is an oncolytic herpes simplex virus-1 with a unique genomic structure that has non-engineered deletions and insertions accompanied by frame-shift mutations, in contrast to the majority of engineered OVs. At the genetic level, HF10 naturally lacks the expression of UL43, UL49.5, UL55, UL56, and latency-associated transcripts, and overexpresses UL53 and UL54. In preclinical studies, HF10 replicated efficiently within tumor cells with extensive cytolytic effects and induced increased numbers of activated CD4+ and CD8+ T cells and natural killer cells within the tumor, leading to a significant reduction in tumor growth and prolonged survival rates. Investigator-initiated clinical studies of HF10 have been completed in recurrent breast carcinoma, head and neck cancer, and unresectable pancreatic cancer in Japan. Phase I trials were subsequently completed in refractory superficial cancers and melanoma in the United States. HF10 has been demonstrated to have a high safety margin with low frequency of adverse effects in all treated patients. Interestingly, HF10 antigens were detected in pancreatic carcinoma over 300 days after treatment with infiltration of CD4+ and CD8+ T cells, which enhanced the immune response. To date, preliminary results from a Phase II trial have indicated that HF10 in combination with ipilimumab (anti-CTLA-4 is safe and well tolerated, with high antitumor efficacy. Improvement of the effect of ipilimumab was observed in patients with stage IIIb, IIIc, or IV unresectable or metastatic melanoma. This review provides a concise description of the genomic functional organization of HF10 compared with talimogene laherparepvec. Furthermore, this review focuses on HF10 in cancer treatment as monotherapy as well as in combination therapy

  2. Meningeal myeloma deposits adversely impact the therapeutic index of an oncolytic VSV.

    Science.gov (United States)

    Yarde, D N; Naik, S; Nace, R A; Peng, K-W; Federspiel, M J; Russell, S J

    2013-11-01

    Vesicular stomatitis virus (VSV) is neuropathogenic in rodents but can be attenuated 50-fold by engineering the mouse interferon-beta (IFN-β) gene into its genome. Intravenously administered VSVs encoding IFN-β have potent activity against subcutaneous tumors in the 5TGM1 mouse myeloma model, without attendant neurotoxicity. However, when 5TGM1 tumor cells were seeded intravenously, virus-treated mice with advanced myeloma developed clinical signs suggestive of meningoencephalitis. Co-administration of a known active antimyeloma agent did not prolong survival, further suggesting that deaths were due to viral toxicity, not tumor burden. Histological analysis revealed that systemically administered 5TGM1 cells seed to the CNS, forming meningeal tumor deposits, and that VSV infects and destroys these tumors. Death is presumably a consequence of meningeal damage and/or direct transmission of virus to adjacent neural tissue. In light of these studies, extreme caution is warranted in clinical testing of attenuated VSVs, particularly in patients with CNS tumor deposits.

  3. Meningeal myeloma deposits adversely impact the therapeutic index of an oncolytic VSV

    Science.gov (United States)

    Yarde, Danielle N.; Naik, Shruthi; Nace, Rebecca A.; Peng, Kah-Whye; Federspiel, Mark J.; Russell, Stephen J.

    2013-01-01

    Vesicular Stomatitis Virus (VSV) is neuropathogenic in rodents but can be attenuated 50-fold by engineering the mouse interferon-beta (IFN-β) gene into its genome. Intravenously administered VSVs encoding IFN-β have potent activity against subcutaneous tumors in the 5TGM1 mouse myeloma model, without attendant neurotoxicity. However, when 5TGM1 tumor cells were seeded intravenously, virus-treated mice with advanced myeloma developed clinical signs suggestive of meningoencephalitis. Co-administration of a known active antimyeloma agent did not prolong survival, further suggesting that deaths were due to viral toxicity, not tumor burden. Histological analysis revealed that systemically administered 5TGM1 cells seed to the CNS forming meningeal tumor deposits and that VSV infects and destroys these tumors. Death is presumably a consequence of meningeal damage and/or direct transmission of virus to adjacent neural tissue. In light of these studies, extreme caution is warranted in clinical testing of attenuated VSVs, particularly in patients with CNS tumor deposits. PMID:24176894

  4. SEISMIC ATTENUATION FOR RESERVOIR CHARACTERIZATION

    Energy Technology Data Exchange (ETDEWEB)

    Joel Walls; M.T. Taner; Gary Mavko; Jack Dvorkin

    2002-04-01

    Wave-induced variations of pore pressure in a partially-saturated reservoir result in oscillatory liquid flow. The viscous losses during this flow are responsible for wave attenuation. The same viscous effects determine the changes in the dynamic bulk modulus of the system versus frequency. These changes are necessarily linked to attenuation via the causality condition. We analytically quantify the frequency dependence of the bulk modulus of a partially saturated rock by assuming that saturation is patchy and then link these changes to the inverse quality factor. As a result, the P-wave attenuation is quantitatively linked to saturation and thus can serve as a saturation indicator.

  5. Recombinant vaccines and the development of new vaccine strategies

    Energy Technology Data Exchange (ETDEWEB)

    Nascimento, I.P.; Leite, L.C.C. [Centro de Biotecnologia, Instituto Butantan, São Paulo, SP (Brazil)

    2012-09-07

    Vaccines were initially developed on an empirical basis, relying mostly on attenuation or inactivation of pathogens. Advances in immunology, molecular biology, biochemistry, genomics, and proteomics have added new perspectives to the vaccinology field. The use of recombinant proteins allows the targeting of immune responses focused against few protective antigens. There are a variety of expression systems with different advantages, allowing the production of large quantities of proteins depending on the required characteristics. Live recombinant bacteria or viral vectors effectively stimulate the immune system as in natural infections and have intrinsic adjuvant properties. DNA vaccines, which consist of non-replicating plasmids, can induce strong long-term cellular immune responses. Prime-boost strategies combine different antigen delivery systems to broaden the immune response. In general, all of these strategies have shown advantages and disadvantages, and their use will depend on the knowledge of the mechanisms of infection of the target pathogen and of the immune response required for protection. In this review, we discuss some of the major breakthroughs that have been achieved using recombinant vaccine technologies, as well as new approaches and strategies for vaccine development, including potential shortcomings and risks.

  6. Recombinant vaccines and the development of new vaccine strategies

    Directory of Open Access Journals (Sweden)

    I.P. Nascimento

    2012-12-01

    Full Text Available Vaccines were initially developed on an empirical basis, relying mostly on attenuation or inactivation of pathogens. Advances in immunology, molecular biology, biochemistry, genomics, and proteomics have added new perspectives to the vaccinology field. The use of recombinant proteins allows the targeting of immune responses focused against few protective antigens. There are a variety of expression systems with different advantages, allowing the production of large quantities of proteins depending on the required characteristics. Live recombinant bacteria or viral vectors effectively stimulate the immune system as in natural infections and have intrinsic adjuvant properties. DNA vaccines, which consist of non-replicating plasmids, can induce strong long-term cellular immune responses. Prime-boost strategies combine different antigen delivery systems to broaden the immune response. In general, all of these strategies have shown advantages and disadvantages, and their use will depend on the knowledge of the mechanisms of infection of the target pathogen and of the immune response required for protection. In this review, we discuss some of the major breakthroughs that have been achieved using recombinant vaccine technologies, as well as new approaches and strategies for vaccine development, including potential shortcomings and risks.

  7. Evaluation of the infection and transmission of wild type and recombinant strains of Newcastle disease virus in Japanese Quail

    Science.gov (United States)

    Newcastle disease virus (NDV) causes a range of clinical disease ranging from asymptomatic infection to severe disease with high mortality. Vaccination for NDV is practiced almost worldwide in commercial chickens. Attenuated live vaccines are most commonly used, with recombinant vaccines becoming ...

  8. Safety and biodistribution of a double-deleted oncolytic vaccinia virus encoding CD40 ligand in laboratory Beagles

    Directory of Open Access Journals (Sweden)

    Karoliina Autio

    2014-01-01

    Full Text Available We evaluated adverse events, biodistribution and shedding of oncolytic vaccinia virus encoding CD40 ligand in two Beagles, in preparation for a phase 1 trial in canine cancer patients. Dog 1 received one dose of vaccinia virus and was euthanized 24 hours afterwards, while dog 2 received virus four times once weekly and was euthanized 7 days after that. Dogs were monitored for adverse events and underwent a detailed postmortem examination. Blood, saliva, urine, feces, and organs were collected for virus detection. Dog 1 had mild fever and lethargy while dog 2 experienced a possible seizure 5.5 hours after first virus administration. Viral DNA declined quickly in the blood after virus administration in both dogs but was still detectable 1 week later by quantitative polymerase chain reaction. Only samples taken directly after virus infusion contained infectious virus. Small amounts of viral DNA, but no infectious virus, were detected in a few saliva and urine samples. Necropsies did not reveal any relevant pathological changes and virus DNA was detected mainly in the spleen. The dogs in the study did not have cancer, and thus adverse events could be more common and viral load higher in dogs with tumors which allow viral amplification.

  9. 2-aminopurine enhances the oncolytic activity of an E1b-deleted adenovirus in hepatocellular carcinoma cells.

    Science.gov (United States)

    Sharon, David; Schümann, Michael; MacLeod, Sheena; McPherson, Robyn; Chaurasiya, Shyambabu; Shaw, Andrew; Hitt, Mary M

    2013-01-01

    Adenoviruses with deletions of viral genes have been extensively studied as potential cancer therapeutics. Although a high degree of cancer selectivity has been demonstrated with these conditionally replicating adenoviruses, low levels of virus replication can be detected in normal cells. Furthermore, these mutations were also found to reduce the activity of the replicating viruses in certain cancer cells. Recent studies have shown that co-administration of chemotherapeutic drugs may increase the activity of these viruses without affecting their specificity. We constructed an adenovirus with deletions of both the E1b and the VA-RNA genes and found that replication of this virus was selective for human hepatocellular carcinoma (HCC) cell lines when compared to normal cell lines. Furthermore, we show that 2-aminopurine (2'AP) treatment selectively enhanced virus replication and virus-mediated death of HCC cells. 2'AP did not compensate for the loss of VA-RNA activities, but rather the loss of an E1b-55K activity, such as the DNA damage response, suggesting that co-administration of 2'AP derivatives that block host DNA damage response, may increase the oncolytic activity of AdΔE1bΔVA without reducing its selectivity for HCC cells.

  10. 2-aminopurine enhances the oncolytic activity of an E1b-deleted adenovirus in hepatocellular carcinoma cells.

    Directory of Open Access Journals (Sweden)

    David Sharon

    Full Text Available Adenoviruses with deletions of viral genes have been extensively studied as potential cancer therapeutics. Although a high degree of cancer selectivity has been demonstrated with these conditionally replicating adenoviruses, low levels of virus replication can be detected in normal cells. Furthermore, these mutations were also found to reduce the activity of the replicating viruses in certain cancer cells. Recent studies have shown that co-administration of chemotherapeutic drugs may increase the activity of these viruses without affecting their specificity. We constructed an adenovirus with deletions of both the E1b and the VA-RNA genes and found that replication of this virus was selective for human hepatocellular carcinoma (HCC cell lines when compared to normal cell lines. Furthermore, we show that 2-aminopurine (2'AP treatment selectively enhanced virus replication and virus-mediated death of HCC cells. 2'AP did not compensate for the loss of VA-RNA activities, but rather the loss of an E1b-55K activity, such as the DNA damage response, suggesting that co-administration of 2'AP derivatives that block host DNA damage response, may increase the oncolytic activity of AdΔE1bΔVA without reducing its selectivity for HCC cells.

  11. The oncolytic adenovirus Δ24-RGD in combination with cisplatin exerts a potent anti-osteosarcoma activity.

    Science.gov (United States)

    Martinez-Velez, Naiara; Xipell, Enric; Jauregui, Patricia; Zalacain, Marta; Marrodan, Lucía; Zandueta, Carolina; Vera, Beatriz; Urquiza, Leire; Sierrasesúmaga, Luis; Julián, Mikel San; Toledo, Gemma; Fueyo, Juan; Gomez-Manzano, Candelaria; Torre, Wensceslao; Lecanda, Fernando; Patiño-García, Ana; Alonso, Marta M

    2014-10-01

    Osteosarcoma is the most common malignant bone tumor in children and adolescents. The presence of metastases and the lack of response to conventional treatment are the major adverse prognostic factors. Therefore, there is an urgent need for new treatment strategies that overcome both of these problems. Our purpose was to elucidate whether the use of the oncolytic adenovirus Δ24-RGD alone or in combination with standard chemotherapy would be effective, in vitro and in vivo, against osteosarcoma. Our results showed that Δ24-RGD exerted a potent antitumor effect against osteosarcoma cell lines that was increased by the addition of cisplatin. Δ24-RGD osteosarcoma treatment resulted in autophagy in vitro that was further enhanced when combined with cisplatin. Of importance, administration of Δ24-RGD and/or cisplatin, in novel orthotopic and two lung metastatic models in vivo resulted in a significant reduction of tumor burden meanwhile maintaining a safe toxicity profile. Together, our data underscore the potential of Δ24-RGD to become a realistic therapeutic option for primary and metastatic pediatric osteosarcoma. Moreover, this study warrants a future clinical trial to evaluate the safety and efficacy of Δ24-RGD for this devastating disease. © 2014 American Society for Bone and Mineral Research.

  12. Probing the Molecular Mechanisms Governing the Oncolytic Activity of Paeonia suffruticosa on Triple-negative Breast Cancer Cells In Vitro.

    Science.gov (United States)

    Kim, Dongyeon; Radin, Daniel; Leonardi, Donna

    2017-09-01

    Extracts of Paeonia suffruticosa are traditionally used in Chinese medicine to increase blood flow. Recently, this extract has been shown to possess anti-tumor and anti-inflammatory properties, though this mechanism remains unknown. In the current work, we prepared extracts of P. suffruticosa and analyzed their effects on MDA-MB-231 triple-negative breast cancer cells. Varying concentrations of an aqueous extract of P. suffruticosa was administered to MDA-MB-231. An MTS assay was used to determine the cell viability. Cytokine production was investigated through enzyme-linked immunosorbent assay (ELISA). Caspase-Glo assays were performed to measure caspase 3/7, 8 and 9 to analyze anti-apoptotic effects. MTS assay for cell viability revealed that the extract increased viability at low concentrations (0.6 mg/ml) and decreased viability observed at concentrations ≥2.5 mg/ml (ppppP. suffruticosa extract reduced MDA-MB-231 viability by >60% (pp>0.05), suggesting a selective oncolytic effect. P. suffruticosa extract has the ability to modulate the production of several tumor suppressive cytokines, induce intrinsic apoptosis and has the capability of reducing cancer burden while sparing healthy tissue. Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

  13. Combination of Oncolytic Herpes Simplex Viruses Armed with Angiostatin and IL-12 Enhances Antitumor Efficacy in Human Glioblastoma Models

    Directory of Open Access Journals (Sweden)

    Wei Zhang

    2013-06-01

    Full Text Available Oncolytic herpes simplex virus (oHSV can potentially spread throughout the tumor, reach isolated infiltrating cells, kill them, and deliver anticancer agents. However, the host responds to oHSV by inducing intratumoral infiltration of macrophages that can engulf the virus, limiting the potential of this therapeutic strategy. Hypervascularity is a pathognomonic feature of glioblastoma (GBM and is a promising therapeutic target. Antiangiogenic treatments have multiple benefits, including the capacity to increase oHSV efficacy by suppressing macrophage extravasation and infiltration into the tumor. Angiostatin is an antiangiogenic polypeptide, and interleukin-12 (IL-12 is an immunostimulatory cytokine with strong antiangiogenic effects. Clinical use of each has been limited by delivery issues and systemic toxicity.We tested a combination treatment strategy using oHSVs expressing angiostatin (G47Δ-mAngio and IL-12 (G47Δ-mIL12 in two orthotopic human GBMmodels. Intratumoral injection of G47Δ-mAngio and G47Δ-mIL12 in mice bearing intracranial U87 or tumors derived from glioblastoma stem cells significantly prolonged survival compared to each armed oHSV alone. This was associated with increased antiangiogenesis and virus spread and decreased macrophages. These data support the paradigm of using oHSV expressing different antiangiogenic agents and show for the first time that oHSVs expressing angiostatin and IL-12 can improve efficacy in human GBM models.

  14. Selective purging of human multiple myeloma cells from autologous stem cell transplant grafts using oncolytic myxoma virus

    Science.gov (United States)

    Bartee, Eric; Chan, Winnie S.; Moreb, Jan S.; Cogle, Christopher R.; McFadden, Grant

    2012-01-01

    Autologous stem cell transplantation (ASCT) and novel therapies have improved overall survival of patients with multiple myeloma; however, most patients relapse and eventually succumb to their disease. Evidence indicates that residual cancer cells contaminate autologous grafts and may contribute to early relapses after ASCT. Here, we demonstrate that ex vivo treatment with an oncolytic poxvirus called myxoma virus results in specific elimination of human myeloma cells by inducing rapid cellular apoptosis while fully sparing normal hematopoietic stem and progenitor cells (HSPCs). The specificity of this elimination is based on strong binding of the virus to myeloma cells coupled with an inability of the virus to bind or infect CD34+ HSPCs. These two features allow myxoma to readily identify and distinguish even low levels of myeloma cells in complex mixtures. This ex vivo MYXV treatment also effectively inhibits systemic in vivo engraftment of human myeloma cells into immunodeficient mice and results in efficient elimination of primary CD138+ myeloma cells contaminating patient hematopoietic cell products. We conclude that ex vivo myxoma treatment represents a safe and effective method to selectively eliminate myeloma cells from hematopoietic autografts prior to reinfusion. PMID:22516053

  15. Prevention of EBV lymphoma development by oncolytic myxoma virus in a murine xenograft model of post-transplant lymphoproliferative disease.

    Science.gov (United States)

    Kim, Manbok; Rahman, Masmudur M; Cogle, Christopher R; McFadden, Grant

    2015-07-10

    Epstein-Barr virus (EBV) has been associated with a variety of epithelial and hematologic malignancies, including B-, T- and NK cell-lymphomas, Hodgkin's disease (HD), post-transplant lymphoproliferative diseases (LPDs), nasopharyngeal and gastric carcinomas, smooth muscle tumors, and HIV-associated lymphomas. Currently, treatment options for EBV-associated malignancies are limited. We have previously shown that myxoma virus specifically targets various human solid tumors and leukemia cells in a variety of animal models, while sparing normal human or murine tissues. Since transplant recipients of bone marrow or solid organs often develop EBV-associated post-transplant LPDs and lymphoma, myxoma virus may be of utility to prevent EBV-associated malignancies in immunocompromised transplant patients where treatment options are frequently limited. In this report, we demonstrate the safety and efficacy of myxoma virus purging as a prophylactic strategy for preventing post-transplant EBV-transformed human lymphomas, using a highly immunosuppressed mouse xenotransplantation model. This provides support for developing myxoma virus as a potential oncolytic therapy for preventing EBV-associated LPDs following transplantation of bone marrow or solid organ allografts. Copyright © 2015 Elsevier Inc. All rights reserved.

  16. Clinical development of talimogene laherparepvec (T-VEC): a modified herpes simplex virus type-1-derived oncolytic immunotherapy.

    Science.gov (United States)

    Harrington, Kevin J; Puzanov, Igor; Hecht, J Randolph; Hodi, F Stephen; Szabo, Zsolt; Murugappan, Swami; Kaufman, Howard L

    2015-01-01

    Tumor immunotherapy is emerging as a promising new treatment option for patients with cancer. T-VEC is an intralesional oncolytic virus therapy based on a modified herpes simplex virus type-1. T-VEC selectively targets tumor cells, causing regression in injected lesions and inducing immunologic responses that mediate regression at uninjected/distant sites. In a randomized phase III trial, T-VEC met its primary endpoint of improving the durable response rate vs granulocyte-macrophage colony-stimulating factor in patients with unresectable melanoma. Responses were observed in injected and uninjected regional and visceral lesions. Exploratory analyses suggested survival differences in favor of T-VEC in patients with untreated or stage IIIB/IIIC/IVM1a disease. T-VEC was generally well tolerated, the most common adverse events being flu-like symptoms. Here, we overview recent advances in cancer immunotherapy, focusing on the clinical development of T-VEC, from first-in-human studies and studies in other cancer types, to ongoing combination trials with checkpoint inhibitors.

  17. Institutional Animal Care and Use Committee Considerations Regarding the Use of Virus-Induced Carcinogenesis and Oncolytic Viral Models.

    Science.gov (United States)

    Lewis, Stephanie D; Hickman-Davis, Judy M; Bergdall, Valerie K

    2016-01-01

    The use of virus-induced carcinogenesis and oncologic experimental animal models is essential in understanding the mechanisms of cancer development to advance prevention, diagnosis, and treatment methods. The Institutional Animal Care and Use Committee (IACUC) is responsible for both the complex philosophical and practical considerations associated with animal models of cancer. Animal models of cancer carry their own unique issues that require special consideration from the IACUC. Many of the considerations to be discussed apply to cancer models in general; specific issues related to viral carcinogenesis or oncolytic viruses will be specifically discussed as they arise. Responsible animal use integrates good science, humane care, and regulatory compliance. To meet those standards, the IACUC, in conjunction with the research investigator and attending veterinarian, must address a wide range of issues, including animal model selection, cancer model selection, humane end point considerations, experimental considerations, postapproval monitoring, reporting requirements, and animal management and personnel safety considerations. © The Author 2016. Published by Oxford University Press on behalf of the Institute for Laboratory Animal Research. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  18. Integrated Microfluidic Variable Optical Attenuator

    Science.gov (United States)

    2005-11-28

    indices , the optical output power is gradually attenuated. We obtain a maximum attenuation of 28 dB when the fluid refractive index changes from 1.557 to...Electron. 23, pp. 1348-1354 (2005). 14. J. M. Ruano, V. Benoit, J. S. Aitchison , and J. M. Cooper, “Flame hydrolysis deposition of glass on silicon for...different refractive indices flowing in a microfluidic channel as the cladding for a segment of straight optical waveguide. Recently, the integration of

  19. Dissociative Recombination of Complex Ions

    Science.gov (United States)

    Mitchell, J. Brian A.

    1999-10-01

    The FALP-MS apparatus at the University of Rennes allows the measurement of rate coefficients for the recombination of molecular ions to be made (at 300K) even though several ions may be present in the afterglow. The recombination of a number of hydrocarbon ions derived from alkane ( Lehfaoui et al. J. Chem. Phys. 106, 5406, 1997.), alkene ( Rebrion-Rowe et al. J. Chem. Phys. 108, 7185, 1998.) and aromatic (Rebrion-Rowe et al. (Submitted to J. Chem. Phys.)) parent molecules has been studied. Despite the wide range of complexity of these compounds, the measured recombination rates are remarkably similar having values in the range of 4-10-7 cm^3.s-1. Plans are being laid for a new version of this apparatus that will allow pre-prepared ions to be injected into the inert buffer gas flow. This will allow reactive ions to be studied as well as halogen containing ions whose recombination rates would normally be masked by electron attachment to their parent gases in a conventional flowing afterglow apparatus. A high temperature modification to the CRESU supersonic flow apparatus (J.L. Le Garrec et al. J. Chem. Phys. 107, 54, 1997.) in our laboratory will allow electron attachment to radicals to be studied by means of the mass spectrometric detection of products, Langmuir probe measurement of the electron density in the flow and Laser Induced Fluorescent identification of the radical species. Such measurements are needed for the modeling of semiconductor processing plasmas.

  20. Influenza Vaccine, Inactivated or Recombinant

    Science.gov (United States)

    ... die from flu, and many more are hospitalized.Flu vaccine can:keep you from getting flu, make flu ... What is inactivated or recombinant influenza vaccine?A dose of flu vaccine is recommended every flu season. Children 6 months through 8 years of age may need two ...

  1. Molecular Mechanism for Genetic Recombination

    Science.gov (United States)

    Sobell, Henry M.

    1972-01-01

    Symmetry considerations of proteinnucleic acid interaction suggest the existence of an alternate branched configuration for DNA induced by binding specific structural proteins to symmetrically arranged polynucleotide base sequences. The concept that such sequences exist at the ends of genes or operons leads to a molecular model for genetic recombination in eukaryotic cells. PMID:4115953

  2. Genetic recombination and molecular evolution.

    Science.gov (United States)

    Charlesworth, B; Betancourt, A J; Kaiser, V B; Gordo, I

    2009-01-01

    Reduced rates of genetic recombination are often associated with reduced genetic variability and levels of adaptation. Several different evolutionary processes, collectively known as Hill-Robertson (HR) effects, have been proposed as causes of these correlates of recombination. Here, we use DNA sequence polymorphism and divergence data from the noncrossing over dot chromosome of Drosophila to discriminate between two of the major forms of HR effects: selective sweeps and background selection. This chromosome shows reduced levels of silent variability and reduced effectiveness of selection. We show that neither model fits the data on variability. We propose that, in large genomic regions with restricted recombination, HR effects among nonsynonymous mutations undermine the effective strength of selection, so that their background selection effects are weakened. This modified model fits the data on variability and also explains why variability in very large nonrecombining genomes is not completely wiped out. We also show that HR effects of this type can produce an individual selection advantage to recombination, as well as greatly reduce the mean fitness of nonrecombining genomes and genomic regions.

  3. Recombination in immunoglobulin gene loci

    Directory of Open Access Journals (Sweden)

    Komisarenko S. V.

    2009-02-01

    Full Text Available Gene network of the lymphoid cell differentiation coordinates precisely the recombination process in immunoglobulin gene loci. In our opinion, cellular microRNAs can contribute to the allelic exclusion through microRNA-directed DNA methylation and participate in retargeting recombinases activity from the gene loci of heavy immunoglobulin chains to the gene loci of light chains

  4. The strength of the T cell response against a surrogate tumor antigen induced by oncolytic VSV therapy does not correlate with tumor control.

    Science.gov (United States)

    Janelle, Valérie; Langlois, Marie-Pierre; Lapierre, Pascal; Charpentier, Tania; Poliquin, Laurent; Lamarre, Alain

    2014-06-01

    Cancer therapy using oncolytic viruses has gained interest in the last decade. Vesicular stomatitis virus is an attractive candidate for this alternative treatment approach. The importance of the immune response against tumor antigens in virotherapy efficacy is now well recognized, however, its relative contribution versus the intrinsic oncolytic capacity of viruses has been difficult to evaluate. To start addressing this question, we compared glycoprotein and matrix mutants of vesicular stomatitis virus (VSV), showing different oncolytic potentials for B16/B16gp33 melanoma tumor cells in vitro, with the wild-type virus in their ability to induce tumor-specific CD8(+) T cell responses and control tumor progression in vivo. Despite the fact that wild-type and G mutants induced a stronger gp33-specific immune response compared to the MM51R mutant, all VSV strains showed a similar capacity to slow down tumor progression. The effectiveness of the matrix mutant treatment proved to be CD8(+) dependent and directed against tumor antigens other than gp33 since adoptive transfer of isolated CD8(+) T lymphocytes from treated B16gp33-bearing mice resulted in significant protection of naive mice against challenge with the parental tumor. Remarkably, the VSV matrix mutant induced the upregulation of major histocompatibility class-I antigen at the tumor cell surface thus favoring recognition by CD8(+) T cells. These results demonstrate that VSV mutants induce an antitumor immune response using several mechanisms. A better understanding of these mechanisms will prove useful for the rational design of viruses with improved therapeutic efficacy.

  5. In vitro screen of a small molecule inhibitor drug library identifies multiple compounds that synergize with oncolytic myxoma virus against human brain tumor-initiating cells.

    Science.gov (United States)

    McKenzie, Brienne A; Zemp, Franz J; Pisklakova, Alexandra; Narendran, Aru; McFadden, Grant; Lun, Xueqing; Kenchappa, Rajappa S; Kurz, Ebba U; Forsyth, Peter A

    2015-08-01

    Brain tumor-initiating cells (BTICs) are stem-like cells hypothesized to form a disease reservoir that mediates tumor recurrence in high-grade gliomas. Oncolytic virotherapy uses replication-competent viruses to target and kill malignant cells and has been evaluated in clinic for glioma therapy with limited results. Myxoma virus (MyxV) is a safe and highly effective oncolytic virus (OV) in conventional glioma models but, as seen with other OVs, is only modestly effective for patient-derived BTICs. The objective of this study was to determine whether MyxV treatment against human BTICs could be improved by combining chemotherapeutics and virotherapy. A 73-compound library of drug candidates in clinical use or preclinical development was screened to identify compounds that sensitize human BTICs to MyxV treatment in vitro, and synergy was evaluated mathematically in lead compounds using Chou-Talalay analyses. The effects of combination therapy on viral gene expression and viral replication were also assessed. Eleven compounds that enhance MyxV efficacy were identified, and 6 were shown to synergize with the virus using Chou-Talalay analyses. Four of the synergistic compounds were shown to significantly increase viral gene expression, indicating a potential mechanism for synergy. Three highly synergistic compounds (axitinib, a VEGFR inhibitor; rofecoxib, a cyclooxygenase-2 inhibitor; and pemetrexed, a folate anti-metabolite) belong to classes of compounds that have not been previously shown to synergize with oncolytic viruses in vitro. This study has identified multiple novel drug candidates that synergistically improve MyxV efficacy in a preclinical BTIC glioma model. © The Author(s) 2015. Published by Oxford University Press on behalf of the Society for Neuro-Oncology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  6. Increased pathogenicity in a pseudorecombinant bipartite geminivirus correlates with intermolecular recombination.

    OpenAIRE

    Hou, Y M; Gilbertson, R L

    1996-01-01

    Most whitefly-transmitted geminiviruses possess bipartite DNA genomes, and this feature may facilitate viral evolution through pseudorecombination and/or recombination. To test this hypothesis, the DNA-A and DNA-B components of the geminiviruses bean dwarf mosaic virus (BDMV) and tomato mottle virus (ToMoV) were exchanged, and the resultant pseudorecombinants were serially passaged through plants. Both pseudorecombinants were infectious in Nicotiana benthamiana but induced attenuated symptoms...

  7. A selectable and excisable marker system for the rapid creation of recombinant poxviruses.

    Directory of Open Access Journals (Sweden)

    Julia L Rintoul

    Full Text Available Genetic manipulation of poxvirus genomes through attenuation, or insertion of therapeutic genes has led to a number of vector candidates for the treatment of a variety of human diseases. The development of recombinant poxviruses often involves the genomic insertion of a selectable marker for purification and selection purposes. The use of marker genes however inevitably results in a vector that contains unwanted genetic information of no therapeutic value.Here we describe an improved strategy that allows for the creation of marker-free recombinant poxviruses of any species. The Selectable and Excisable Marker (SEM system incorporates a unique fusion marker gene for the efficient selection of poxvirus recombinants and the Cre/loxP system to facilitate the subsequent removal of the marker. We have defined and characterized this new methodological tool by insertion of a foreign gene into vaccinia virus, with the subsequent removal of the selectable marker. We then analyzed the importance of loxP orientation during Cre recombination, and show that the SEM system can be used to introduce site-specific deletions or inversions into the viral genome. Finally, we demonstrate that the SEM strategy is amenable to other poxviruses, as demonstrated here with the creation of an ectromelia virus recombinant lacking the EVM002 gene.The system described here thus provides a faster, simpler and more efficient means to create clinic-ready recombinant poxviruses for therapeutic gene therapy applications.

  8. Initiation of meiotic recombination in Ustilago maydis

    National Research Council Canada - National Science Library

    Kojic, Milorad; Sutherland, Jeanette H; Pérez-Martín, José; Holloman, William K

    2013-01-01

    .... Ustilago maydis, a biotrophic fungus that parasitizes maize, has long been utilized as an experimental system for studying recombination, but it has not been clear when in the life cycle meiotic recombination initiates. U...

  9. GARD: a genetic algorithm for recombination detection

    National Research Council Canada - National Science Library

    Kosakovsky Pond, Sergei L; Posada, David; Gravenor, Michael B; Woelk, Christopher H; Frost, Simon D W

    2006-01-01

    .... We developed a likelihood-based model selection procedure that uses a genetic algorithm to search multiple sequence alignments for evidence of recombination breakpoints and identify putative recombinant sequences...

  10. Vesicular stomatitis virus expressing interferon-? is oncolytic and promotes antitumor immune responses in a syngeneic murine model of non-small cell lung cancer

    OpenAIRE

    Patel, Manish R.; Jacobson, Blake A.; Ji, Yan; Drees, Jeremy; Tang, Shaogeng; Xiong, Kerry; Wang, Hengbing; Prigge, Jennifer E.; Dash, Alexander S.; Kratzke, Andrea K.; Mesev, Emily; Etchison, Ryan; Federspiel, Mark J.; Russell, Stephen J; Kratzke, Robert A

    2015-01-01

    Vesicular stomatitis virus (VSV) is a potent oncolytic virus for many tumors. VSV that produces interferon-? (VSV-IFN?) is now in early clinical testing for solid tumors. Here, the preclinical activity of VSV and VSV-IFN? against non-small cell lung cancer (NSCLC) is reported. NSCLC cell lines were treated in vitro with VSV expressing green fluorescence protein (VSV-GFP) and VSV-IFN?. VSV-GFP and VSV-IFN? were active against NSCLC cells. JAK/STAT inhibition with ruxolitinib re-sensitized resi...

  11. Enhancing the Oncolytic Activity of CD133-Targeted Measles Virus: Receptor Extension or Chimerism with Vesicular Stomatitis Virus Are Most Effective

    Science.gov (United States)

    Kleinlützum, Dina; Hanauer, Julia D. S.; Muik, Alexander; Hanschmann, Kay-Martin; Kays, Sarah-Katharina; Ayala-Breton, Camilo; Peng, Kah-Whye; Mühlebach, Michael D.; Abel, Tobias; Buchholz, Christian J.

    2017-01-01

    Therapy resistance and tumor recurrence are often linked to a small refractory and highly tumorigenic subpopulation of neoplastic cells, known as cancer stem cells (CSCs). A putative marker of CSCs is CD133 (prominin-1). We have previously described a CD133-targeted oncolytic measles virus (MV-CD133) as a promising approach to specifically eliminate CD133-positive tumor cells. Selectivity was introduced at the level of cell entry by an engineered MV hemagglutinin (H). The H protein was blinded for its native receptors and displayed a CD133-specific single-chain antibody fragment (scFv) as targeting domain. Interestingly, MV-CD133 was more active in killing CD133-positive tumors than the unmodified MV-NSe despite being highly selective for its target cells. To further enhance the antitumoral activity of MV-CD133, we here pursued arming technologies, receptor extension, and chimeras between MV-CD133 and vesicular stomatitis virus (VSV). All newly generated viruses including VSV-CD133 were highly selective in eliminating CD133-positive cells. MV-CD46/CD133 killed in addition CD133-negative cells being positive for the MV receptors. In an orthotopic glioma model, MV-CD46/CD133 and MVSCD-CD133, which encodes the super cytosine deaminase, were most effective. Notably, VSV-CD133 caused fatal neurotoxicity in this tumor model. Use of CD133 as receptor could be excluded as being causative. In a subcutaneous tumor model of hepatocellular cancer, VSV-CD133 revealed the most potent oncolytic activity and also significantly prolonged survival of the mice when injected intravenously. Compared to MV-CD133, VSV-CD133 infected a more than 104-fold larger area of the tumor within the same time period. Our data not only suggest new concepts and approaches toward enhancing the oncolytic activity of CD133-targeted oncolytic viruses but also raise awareness about careful toxicity testing of novel virus types. PMID:28695108

  12. Ex Vivo Oncolytic Virotherapy with Myxoma Virus Arms Multiple Allogeneic Bone Marrow Transplant Leukocytes to Enhance Graft versus Tumor

    OpenAIRE

    Lilly, Cameron L.; Villa, Nancy Y.; Lemos de Matos, Ana; Ali, Haider M.; Dhillon, Jess-Karan S.; Hofland, Tom; Rahman, Masmudur M.; Chan, Winnie; Bogen, Bjarne; Cogle, Christopher; McFadden, Grant

    2017-01-01

    Allogeneic stem cell transplant-derived T cells have the potential to seek and eliminate sites of residual cancer that escaped primary therapy. Oncolytic myxoma virus (MYXV) exhibits potent anti-cancer efficacy against human cancers like multiple myeloma (MM) and can arm transplant-derived T cells to become more effective cancer killers in vitro and in an immunodeficient xenotransplant murine model. Here, we tested ex vivo MYXV virotherapy against residual murine MM in immunocompetent mice us...

  13. Is the segmented plasma excitation recombination laser a recombination laser

    Energy Technology Data Exchange (ETDEWEB)

    Apollonov, V.V.; Sirotkin, A.A. (Institut Obshchei Fiziki, Moscow (USSR))

    1989-10-01

    The role of plasmachemical reactions in the formation of active media in lasers with a sectional plasma source for metal vapor is investigated. It is shown that the population of ionic levels in Cd II and Zn II occurs under recharging with He(+) and in the process of Penning ionization. It is found that these processes are more efficient than recombination and electron impact. 13 refs.

  14. Rational plasmid design and bioprocess optimization to enhance recombinant adeno-associated virus (AAV) productivity in mammalian cells.

    Science.gov (United States)

    Emmerling, Verena V; Pegel, Antje; Milian, Ernest G; Venereo-Sanchez, Alina; Kunz, Marion; Wegele, Jessica; Kamen, Amine A; Kochanek, Stefan; Hoerer, Markus

    2016-02-01

    Viral vectors used for gene and oncolytic therapy belong to the most promising biological products for future therapeutics. Clinical success of recombinant adeno-associated virus (rAAV) based therapies raises considerable demand for viral vectors, which cannot be met by current manufacturing strategies. Addressing existing bottlenecks, we improved a plasmid system termed rep/cap split packaging and designed a minimal plasmid encoding adenoviral helper function. Plasmid modifications led to a 12-fold increase in rAAV vector titers compared to the widely used pDG standard system. Evaluation of different production approaches revealed superiority of processes based on anchorage- and serum-dependent HEK293T cells, exhibiting about 15-fold higher specific and volumetric productivity compared to well-established suspension cells cultivated in serum-free medium. As for most other viral vectors, classical stirred-tank bioreactor production is thus still not capable of providing drug product of sufficient amount. We show that manufacturing strategies employing classical surface-providing culture systems can be successfully transferred to the new fully-controlled, single-use bioreactor system Integrity(TM) iCELLis(TM) . In summary, we demonstrate substantial bioprocess optimizations leading to more efficient and scalable production processes suggesting a promising way for flexible large-scale rAAV manufacturing. Copyright © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Attenuation in Superconducting Circular Waveguides

    Directory of Open Access Journals (Sweden)

    K. H. Yeap

    2016-09-01

    Full Text Available We present an analysis on wave propagation in superconducting circular waveguides. In order to account for the presence of quasiparticles in the intragap states of a superconductor, we employ the characteristic equation derived from the extended Mattis-Bardeen theory to compute the values of the complex conductivity. To calculate the attenuation in a circular waveguide, the tangential fields at the boundary of the wall are first matched with the electrical properties (which includes the complex conductivity of the wall material. The matching of fields with the electrical properties results in a set of transcendental equations which is able to accurately describe the propagation constant of the fields. Our results show that although the attenuation in the superconducting waveguide above cutoff (but below the gap frequency is finite, it is considerably lower than that in a normal waveguide. Above the gap frequency, however, the attenuation in the superconducting waveguide increases sharply. The attenuation eventually surpasses that in a normal waveguide. As frequency increases above the gap frequency, Cooper pairs break into quasiparticles. Hence, we attribute the sharp rise in attenuation to the increase in random collision of the quasiparticles with the lattice structure.

  16. Conjugation of gold nanoparticles and recombinant human endostatin modulates vascular normalization via interruption of anterior gradient 2-mediated angiogenesis.

    Science.gov (United States)

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

    2017-07-01

    Several studies have revealed the potential of normalizing tumor vessels in anti-angiogenic treatment. Recombinant human endostatin is an anti-angiogenic agent which has been applied in clinical tumor treatment. Our previous research indicated that gold nanoparticles could be a nanoparticle carrier for recombinant human endostatin delivery. The recombinant human endostatin-gold nanoparticle conjugates normalized vessels, which improved chemotherapy. However, the mechanism of recombinant human endostatin-gold nanoparticle-induced vascular normalization has not been explored. Anterior gradient 2 has been reported to be over-expressed in many malignant tumors and involved in tumor angiogenesis. To date, the precise efficacy of recombinant human endostatin-gold nanoparticles on anterior gradient 2-mediated angiogenesis or anterior gradient 2-related signaling cohort remained unknown. In this study, we aimed to explore whether recombinant human endostatin-gold nanoparticles could normalize vessels in metastatic colorectal cancer xenografts, and we further elucidated whether recombinant human endostatin-gold nanoparticles could interrupt anterior gradient 2-induced angiogenesis. In vivo, it was indicated that recombinant human endostatin-gold nanoparticles increased pericyte expression while inhibit vascular endothelial growth factor receptor 2 and anterior gradient 2 expression in metastatic colorectal cancer xenografts. In vitro, we uncovered that recombinant human endostatin-gold nanoparticles reduced cell migration and tube formation induced by anterior gradient 2 in human umbilical vein endothelial cells. Treatment with recombinant human endostatin-gold nanoparticles attenuated anterior gradient 2-mediated activation of MMP2, cMyc, VE-cadherin, phosphorylation of p38, and extracellular signal-regulated protein kinases 1 and 2 (ERK1/2) in human umbilical vein endothelial cells. Our findings demonstrated recombinant human endostatin-gold nanoparticles might normalize

  17. Attenuation of Semliki Forest Virus Neurovirulence by MicroRNA-Mediated Detargeting

    OpenAIRE

    Ylösmäki, Erkko; Martikainen, Miika; Hinkkanen, Ari; Saksela, Kalle

    2013-01-01

    Artificial target sequences for tissue-specific miRNAs have recently been introduced as a new means for altering the tissue tropism of viral replication. This approach can be used to improve the safety of oncolytic viruses for cancer virotherapy by restricting their replication in unwanted tissues, such as the liver. Semliki Forest virus (SFV) is a positive-strand RNA virus and, similar to the related alphaviruses, like Sindbis virus, has potential as a gene therapy vector and an oncolytic vi...

  18. Microbial factories for recombinant pharmaceuticals

    OpenAIRE

    Domingo-Espín Joan; Ferrer-Miralles Neus; Corchero José; Vázquez Esther; Villaverde Antonio

    2009-01-01

    Abstract Most of the hosts used to produce the 151 recombinant pharmaceuticals so far approved for human use by the Food and Drug Administration (FDA) and/or by the European Medicines Agency (EMEA) are microbial cells, either bacteria or yeast. This fact indicates that despite the diverse bottlenecks and obstacles that microbial systems pose to the efficient production of functional mammalian proteins, namely lack or unconventional post-translational modifications, proteolytic instability, po...

  19. Workshop on Radio Recombination Lines

    CERN Document Server

    1980-01-01

    Since their first detection 15 years ago, radio recombination lines from several elements have been observed in a wide variety of objects including HII regions, planetary nebulae, molecular clouds, the diffuse interstellar medium, and recently, other galaxies. The observations span almost the entire range from 0.1 to 100 GHz, and employ both single­ djsh and aperture synthesis techniques. The theory of radio recombination lines has also advanced strongly, to the point where it is perhaps one of the best-understood in astro­ physics. In a parallel development, it has become possible over the last decade to study these same highly-excited atoms in the laboratory; this work provides further confirmation of the theoretical framework. However there has been continuing controversy over the astrophysical interpre­ tation of radio recombination line observations, especially regarding the role of stimulated emission. A workshop was held in Ottawa on 24-25 August, 1979, bringing together many of the active scientist...

  20. Production systems for recombinant antibodies.

    Science.gov (United States)

    Schirrmann, Thomas; Al-Halabi, Laila; Dübel, Stefan; Hust, Michael

    2008-05-01

    Recombinant antibodies are the fastest growing class of therapeutic proteins. Furthermore, antibodies are key detection reagents in research and diagnostics. The increasing demand for antibodies with regards to amount and quality resulted in the development of a variety of recombinant production systems employing gram-negative and gram-positive bacteria, yeast and filamentous fungi, insect cell lines as well as mammalian cell lines. More recently, antibodies were also successfully produced in transgenic plants and animals. Currently, the production of recombinant antibodies for therapy is performed in mammalian cell lines to reduce the risk of immunogenicity caused by non-human post-translational modifications, in particular glycosylation. However, novel strategies already allow human-like glycosylation patterns in yeast, insect cell lines and transgenic plants. Furthermore, therapeutic strategies not requiring glycosylation of the Fc portion have been conceived, most prominently using bispecific antibodies or scFv fusion proteins, which can be produced in bacteria. Here, we review all current antibody production systems considering their advantages and limitations with respect to intended applications.

  1. A combinational therapy of EGFR-CAR NK cells and oncolytic herpes simplex virus 1 for breast cancer brain metastases.

    Science.gov (United States)

    Chen, Xilin; Han, Jianfeng; Chu, Jianhong; Zhang, Lingling; Zhang, Jianying; Chen, Charlie; Chen, Luxi; Wang, Youwei; Wang, Hongwei; Yi, Long; Elder, J Bradley; Wang, Qi-En; He, Xiaoming; Kaur, Balveen; Chiocca, E Antonio; Yu, Jianhua

    2016-05-10

    Breast cancer brain metastases (BCBMs) are common in patients with metastatic breast cancer and indicate a poor prognosis. These tumors are especially resistant to currently available treatments due to multiple factors. However, the combination of chimeric antigen receptor (CAR)-modified immune cells and oncolytic herpes simplex virus (oHSV) has not yet been explored in this context. In this study, NK-92 cells and primary NK cells were engineered to express the second generation of EGFR-CAR. The efficacies of anti-BCBMs of EGFR-CAR NK cells, oHSV-1, and their combination were tested in vitro and in a breast cancer intracranial mouse model. In vitro, compared with mock-transduced NK-92 cells or primary NK cells, EGFR-CAR-engineered NK-92 cells and primary NK cells displayed enhanced cytotoxicity and IFN-γ production when co-cultured with breast cancer cell lines MDA-MB-231, MDA-MB-468, and MCF-7. oHSV-1 alone was also capable of lysing and destroying these cells. However, a higher cytolytic effect of EGFR-CAR NK-92 cells was observed when combined with oHSV-1 compared to the monotherapies. In the mice intracranially pre-inoculated with EGFR-expressing MDA-MB-231 cells, intratumoral administration of either EGFR-CAR-transduced NK-92 cells or oHSV-1 mitigated tumor growth. Notably, the combination of EGFR-CAR NK-92 cells with oHSV-1 resulted in more efficient killing of MDA-MB-231 tumor cells and significantly longer survival of tumor-bearing mice when compared to monotherapies. These results demonstrate that regional administration of EGFR-CAR NK-92 cells combined with oHSV-1 therapy is a potentially promising strategy to treat BCBMs.

  2. Preclinical Testing of an Oncolytic Parvovirus: Standard Protoparvovirus H-1PV Efficiently Induces Osteosarcoma Cell Lysis In Vitro

    Directory of Open Access Journals (Sweden)

    Carsten Geiss

    2017-10-01

    Full Text Available Osteosarcoma is the most frequent malignant disease of the bone. On the basis of early clinical experience in the 1960s with H-1 protoparvovirus (H-1PV in osteosarcoma patients, this effective oncolytic virus was selected for systematic preclinical testing on various osteosarcoma cell cultures. A panel of five human osteosarcoma cell lines (CAL 72, H-OS, MG-63, SaOS-2, U-2OS was tested. Virus oncoselectivity was confirmed by infecting non-malignant human neonatal fibroblasts and osteoblasts used as culture models of non-transformed mesenchymal cells. H-1PV was found to enter osteosarcoma cells and to induce viral DNA replication, transcription of viral genes, and translation to viral proteins. After H-1PV infection, release of infectious viral particles from osteosarcoma cells into the supernatant indicated successful viral assembly and egress. Crystal violet staining revealed progressive cytomorphological changes in all osteosarcoma cell lines. Infection of osteosarcoma cell lines with the standard H-1PV caused an arrest of the cell cycle in the G2 phase, and these lines had a limited capacity for standard H-1PV virus replication. The cytotoxicity of wild-type H-1PV virus towards osteosarcoma cells was compared in vitro with that of two variants, Del H-1PV and DM H-1PV, previously described as fitness variants displaying higher infectivity and spreading in human transformed cell lines of different origins. Surprisingly, wild-type H-1PV displayed the strongest cytostatic and cytotoxic effects in this analysis and thus seems the most promising for the next preclinical validation steps in vivo.

  3. Nondisjunction of chromosome 15: Origin and recombination

    Energy Technology Data Exchange (ETDEWEB)

    Robinson, W.P.; Bernasconi, F.; Schinzel, A.A.; Mutirangura, A.; Ledbetter, D.H. (Baylor College of Medicine, Houston, TX (United States)); Langlois, S. (Univ. of Britisch Columbia, Vancouver (Canada)); Morris, M.A.; Malcolm, S.

    1993-09-01

    Thirty-two cases of uniparental disomy (UPD), ascertained from Prader-Willi syndrome patients (N=27) and Angelman syndrome patients (N-5), are used to investigate the pattern of recombination associated with nondisjunction of chromosome 15. In addition, the meiotic stage of nondisjunction is inferred by using markers mapping near the centromere. Two basic approaches to the analysis of recombination in specific pairwise intervals along the chromosome. This method shows a significant reduction in recombination for two of five intervals examined. Second, the observed frequency of each recombinant class (i.e., zero, one, two, three, or more observable crossovers) is compared with expected values. This is useful for testing whether the reduction in recombination can be attributed solely to a proportion of cases with no recombination at all (because of asynapsis), with the remaining groups showing normal recombination (or even excess recombination), or whether recombination is uniformly reduced. Analysis of maternal UPD(15) data shows a slight reduction in the multiple-recombinant classes, with a corresponding increase in both the zero- and one-recombinant classes over expected values. The majority, more than 82%, of the extra chromosomes in maternal UPD(15) cases are due to meiotic I nondisjunction events. In contrast, more paternal UPD(15) cases so far examined appear to have a postzygotic origin of the extra paternal chromosome. 33 refs., 1 fig., 7 tabs.

  4. Consequences of recombination on traditional phylogenetic analysis

    DEFF Research Database (Denmark)

    Schierup, M H; Hein, J

    2000-01-01

    We investigate the shape of a phylogenetic tree reconstructed from sequences evolving under the coalescent with recombination. The motivation is that evolutionary inferences are often made from phylogenetic trees reconstructed from population data even though recombination may well occur (mt......DNA or viral sequences) or does occur (nuclear sequences). We investigate the size and direction of biases when a single tree is reconstructed ignoring recombination. Standard software (PHYLIP) was used to construct the best phylogenetic tree from sequences simulated under the coalescent with recombination....... With recombination present, the length of terminal branches and the total branch length are larger, and the time to the most recent common ancestor smaller, than for a tree reconstructed from sequences evolving with no recombination. The effects are pronounced even for small levels of recombination that may...

  5. Recombination-mediated genetic engineering of a bacterial artificial chromosome clone of modified vaccinia virus Ankara (MVA)

    DEFF Research Database (Denmark)

    Cottingham, Matthew G; Andersen, Rikke F; Spencer, Alexandra J

    2008-01-01

    -length, rescuable clones were obtained, which had indistinguishable immunogenicity in mice. One clone was shotgun sequenced and found to be identical to the parent. We employed GalK recombination-mediated genetic engineering (recombineering) of MVA-BAC to delete five selected viral genes. Deletion of C12L, A44L, A...... to infectious virus using a Fowlpox virus helper to supply transcriptional machinery. We apply here a similar approach to the attenuated strain Modified Vaccinia virus Ankara (MVA), now widely used as a safe non-replicating recombinant vaccine vector in mammals, including humans. Four apparently full......-2006). In addition, we found a higher frequency of triple-positive IFN-gamma, TNF-alpha and IL-2 secreting E3-specific CD8+ T-cells 8 weeks after vaccination with MVA lacking B15R. Furthermore, a recombinant vaccine capable of inducing CD8(+) T cells against an epitope from Plasmodium berghei was created using Gal...

  6. Combination of the oral histone deacetylase inhibitor resminostat with oncolytic measles vaccine virus as a new option for epi-virotherapeutic treatment of hepatocellular carcinoma

    Directory of Open Access Journals (Sweden)

    Benjamin Ruf

    Full Text Available Epigenetic therapies such as histone deacetylase inhibitors (HDACi not only have the capability to decrease tumor cell proliferation and to induce tumor cell death but also to silence antiviral response genes. Here, we investigated whether the combination of an oncolytic measles vaccine virus (MeV with the novel oral HDACi resminostat (Res, being in clinical testing in patients with hepatocellular carcinoma (HCC, results in an enhanced efficacy of this epi-virotherapeutic approach compared to any of the two corresponding monotherapies. When testing a panel of human hepatoma cell lines, we found (i a significantly improved rate of primary infections when using oncolytic MeV under concurrent treatment with resminostat, (ii a boosted cytotoxic effect of the epi-virotherapeutic combination (Res + MeV with enhanced induction of apoptosis, and, quite importantly, (iii an absence of any resminostat-induced impairment of MeV replication and spread. Beyond that, we could also show that (iv resminostat, after hepatoma cell stimulation with exogenous human interferon (IFN-β, is able to prevent the induction of IFN-stimulated genes, such as IFIT-1. This finding outlines the possible impact of resminostat on cellular innate immunity, being instrumental in overcoming resistances to MeV-mediated viral oncolysis. Thus, our results support the onset of epi-virotherapeutic clinical trials in patients exhibiting advanced stages of HCC.

  7. KISS1 tumor suppressor restricts angiogenesis of breast cancer brain metastases and sensitizes them to oncolytic virotherapy in vitro.

    Science.gov (United States)

    Platonov, Mikhail E; Borovjagin, Anton V; Kaverina, Natalya; Xiao, Ting; Kadagidze, Zaira; Lesniak, Maciej; Baryshnikova, Marya; Ulasov, Ilya V

    2018-03-28

    KISS1 tumor suppressor protein regulates cancer cell invasion via MMP9 metalloproteinase. Downregulation of KISS1 gene expression promotes progression of breast cancer and melanoma, resulting in the development of distant metastases. In the current study, we investigated whether restoration of KISS1 expression in KISS1-deficient human metastatic breast cancer cells holds potential as an advanced anticancer strategy. To this end we engineered an infectivity-enhanced conditionally-replicative human adenovirus type 5 encoding KISS1 as an "arming" transgene in the Ad5 E3 region for an ectopic KISS1 expression in transduced cancer cells. The oncolytic potential of the vector was examined using brain-invading metastatic clones of CN34 and MDA-MB-231 breast cancer cells, which supported high levels of AdKISS1 replication, correlating with a robust CRAd-mediated cytotoxicity. Secretion of cellular factors responsible for tumor angiogenesis, cell-to-cell communication and anti-tumoral immune responses upon KISS1 expression in breast cancer cells was analyzed by a RayBiotech Kiloplex Quantibody array. Overall, our results indicate that KISS1 transgene expression provides an important benefit for CRAd-mediated cytotoxicity in breast cancer cells and holds potential as an anticancer treatment in conjunction with oncolytic virotherapy of breast and other metastatic cancers. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Attenuation in silica-based optical fibers

    DEFF Research Database (Denmark)

    Wandel, Marie Emilie

    2006-01-01

    In this thesis on attenuation in silica based optical fibers results within three main topics are reported. Spectral attenuation measurements on transmission fibers are performed in the wide wavelength range 290 nm – 1700 nm. The measured spectral attenuation is analyzed with special emphasis...... on absorption peaks in order to investigate the cause of an unusual high attenuation in a series of transmission fibers. Strong indications point to Ni2+ in octahedral coordination as being the cause of the high attenuation. The attenuation of fibers having a high core refractive index is analyzed and the cause...... of the high attenuation measured in such fibers is described as being due to scattering of light on fluctuations of the core diameter. A novel semi-empirical model for predicting the attenuation of high index fibers is presented. The model is shown to be able to predict the attenuation of high index fibers...

  9. [History of vaccination: from empiricism towards recombinant vaccines].

    Science.gov (United States)

    Guérin, N

    2007-01-01

    Two hundreds years after the discovery of the smallpox vaccine, immunization remains one of the most powerful tools of preventive medicine. Immunization was born with Jenner, then Pasteur and expanded during the 19th and 20th century. It started with the empirical observation of cross-immunity between two diseases, cowpox and smallpox. It became a real science, with pathogen isolation, culture and attenuation or inactivation, to prepare a vaccine. Together with clinical and biological efficacy studies and adverse events assessments, it constructed the concept of "vaccinology". Protein conjugation of polyosidic vaccines has made possible early immunisation of infants. Nowadays, recombinant, reassortant, or virus-like particles technologies open the road for new vaccines. Ongoing research opens the way for the development of new vaccines that will help to control transmittable diseases for which we are lacking antimicrobial agents.

  10. Seismic attenuation imaging with causality

    NARCIS (Netherlands)

    Hak, B.; Mulder, W.A.

    2010-01-01

    Seismic data enable imaging of the Earth, not only of velocity and density but also of attenuation contrasts. Unfortunately, the Born approximation of the constant-density visco-acoustic wave equation, which can serve as a forward modelling operator related to seismic migration, exhibits an

  11. Josephson tunnel junction microwave attenuator

    DEFF Research Database (Denmark)

    Koshelets, V. P.; Shitov, S. V.; Shchukin, A. V.

    1993-01-01

    A new element for superconducting electronic circuitry-a variable attenuator-has been proposed, designed, and successfully tested. The principle of operation is based on the change in the microwave impedance of a superconductor-insulator-superconductor (SIS) Josephson tunnel junction when dc bias...

  12. Compact plasmonic variable optical attenuator

    DEFF Research Database (Denmark)

    Leosson, Kristjan; Rosenzveig, Tiberiu; Hermannsson, Pétur Gordon

    2008-01-01

    We demonstrate plasmonic nanowire-based thermo-optic variable optical attenuators operating in the 1525-1625 nm wavelength range. The devices have a footprint as low as 1 mm, extinction ratio exceeding 40 dB, driving voltage below 3 V, and full modulation bandwidth of 1 kHz. The polarization...

  13. Flagella overexpression attenuates Salmonella pathogenesis.

    Directory of Open Access Journals (Sweden)

    Xinghong Yang

    Full Text Available Flagella are cell surface appendages involved in a number of bacterial behaviors, such as motility, biofilm formation, and chemotaxis. Despite these important functions, flagella can pose a liability to a bacterium when serving as potent immunogens resulting in the stimulation of the innate and adaptive immune systems. Previous work showing appendage overexpression, referred to as attenuating gene expression (AGE, was found to enfeeble wild-type Salmonella. Thus, this approach was adapted to discern whether flagella overexpression could induce similar attenuation. To test its feasibility, flagellar filament subunit FliC and flagellar regulon master regulator FlhDC were overexpressed in Salmonella enterica serovar Typhimurium wild-type strain H71. The results show that the expression of either FliC or FlhDC alone, and co-expression of the two, significantly attenuates Salmonella. The flagellated bacilli were unable to replicate within macrophages and thus were not lethal to mice. In-depth investigation suggests that flagellum-mediated AGE was due to the disruptive effects of flagella on the bacterial membrane, resulting in heightened susceptibilities to hydrogen peroxide and bile. Furthermore, flagellum-attenuated Salmonella elicited elevated immune responses to Salmonella presumably via FliC's adjuvant effect and conferred robust protection against wild-type Salmonella challenge.

  14. Flagella Overexpression Attenuates Salmonella Pathogenesis

    Science.gov (United States)

    Yang, Xinghong; Thornburg, Theresa; Suo, Zhiyong; Jun, SangMu; Robison, Amanda; Li, Jinquan; Lim, Timothy; Cao, Ling; Hoyt, Teri; Avci, Recep; Pascual, David W.

    2012-01-01

    Flagella are cell surface appendages involved in a number of bacterial behaviors, such as motility, biofilm formation, and chemotaxis. Despite these important functions, flagella can pose a liability to a bacterium when serving as potent immunogens resulting in the stimulation of the innate and adaptive immune systems. Previous work showing appendage overexpression, referred to as attenuating gene expression (AGE), was found to enfeeble wild-type Salmonella. Thus, this approach was adapted to discern whether flagella overexpression could induce similar attenuation. To test its feasibility, flagellar filament subunit FliC and flagellar regulon master regulator FlhDC were overexpressed in Salmonella enterica serovar Typhimurium wild-type strain H71. The results show that the expression of either FliC or FlhDC alone, and co-expression of the two, significantly attenuates Salmonella. The flagellated bacilli were unable to replicate within macrophages and thus were not lethal to mice. In-depth investigation suggests that flagellum-mediated AGE was due to the disruptive effects of flagella on the bacterial membrane, resulting in heightened susceptibilities to hydrogen peroxide and bile. Furthermore, flagellum-attenuated Salmonella elicited elevated immune responses to Salmonella presumably via FliC’s adjuvant effect and conferred robust protection against wild-type Salmonella challenge. PMID:23056473

  15. Live attenuated measles virus vaccine therapy for locally established malignant glioblastoma tumor cells

    Directory of Open Access Journals (Sweden)

    Al-Shammari AM

    2014-05-01

    , and 120 hours of infection compared with control cells. This study concludes that live attenuated MV Schwarz vaccine induces the oncolytic effect in Iraqi tumor cell line ANGM5 and in the rhabdomyosarcoma cell line through syncytia in tumor cells, which is one of the causes of cell death. The MV vaccine strain has the ability to insert its hemagglutinin protein into the tumor cell surface, leading to modification of the antigenic surface of tumor cells that may induce an antitumor immune response, MV vaccine strain induced cell killing by direct cytolysis and apoptosis induction. These antitumor features may indicate the use of MV in the treatment of glioblastoma.Keywords: virotherapy, glioblastoma multiforme

  16. Construction and characterization of recombinant Japanese encephalitis virus carrying brainspecific miRNA target sequences

    Directory of Open Access Journals (Sweden)

    Wen-yuan CAO

    2014-08-01

    Full Text Available Objective To construct the recombinant Japanese encephalitis virus ( JEV carrying brain-specific miRNA targeting sequences. Methods The target sequences of brain-specific miR-124 and miR-125 were introduced into the infectious cDNA clone of JEV to generate recombinant plasmids based on reverse genetics technology. The recombinant plasmids were linearized with Xho Ⅰ and served as templates of transcription with SP6 RNA polymerase to generate infectious viral RNA. The RNA transcripts were then transfected into BHK-21 cells, and the supernatant was obtained after incubated at 37℃, 5% CO2 for 3 days. The cytopathic changes of BHK-21 cells inoculated with the supernatant were observed after one passage. The rescued viruses carrying miRNA target sequences were validated by RT-PCR, standard plaque forming test on BHK-21 cells and growth curves analysis. Results Two recombinant viruses carrying miR-124 or miR-125 target sequence were rescued, respectively. The insertion of miRNA target sequences was confirmed by DNA sequencing. The rescued viruses yielded similar plaque morphology and replication efficiency compared with wild type JEV. Conclusion The recombinant JEV containing brain-specific miRNA target sequences can be obtained by reverse genetics technique, which could be used in further studies of miRNA-mediated tissue-specific attenuation mechanism of JEV. DOI: 10.11855/j.issn.0577-7402.2014.06.01

  17. CRMAGE: CRISPR Optimized MAGE Recombineering

    DEFF Research Database (Denmark)

    Ronda, Carlotta; Pedersen, Lasse Ebdrup; Sommer, Morten Otto Alexander

    2016-01-01

    A bottleneck in metabolic engineering and systems biology approaches is the lack of efficient genome engineering technologies. Here, we combine CRISPR/Cas9 and λ Red recombineering based MAGE technology (CRMAGE) to create a highly efficient and fast method for genome engineering of Escherichia coli...... that are assembled by a USER-cloning approach enabling quick and cost efficient gRNA replacement. CRMAGE furthermore utilizes CRISPR/Cas9 for efficient plasmid curing, thereby enabling multiple engineering rounds per day. To facilitate the design process, a web-based tool was developed to predict both the λ Red...

  18. Oral administration of a recombinant attenuated Yersinia pseudotuberculosis strain elicits protective immunity against plague.

    Science.gov (United States)

    Sun, Wei; Sanapala, Shilpa; Rahav, Hannah; Curtiss, Roy

    2015-11-27

    A Yersinia pseudotuberculosis PB1+ (Yptb PB1+) mutant strain combined with chromosome insertion of the caf1R-caf1A-caf1M-caf1 operon and deletions of yopJ and yopK, χ10068 [pYV-ω2 (ΔyopJ315 ΔyopK108) ΔlacZ044::caf1R-caf1M-caf1A-caf1] was constructed. Results indicated that gene insertion and deletion did not affect the growth rate of χ10068 compared to wild-type Yptb cultured at 26 °C. In addition, the F1 antigen in χ10068 was synthesized and secreted on the surface of bacteria at 37 °C (mammalian body temperature), not at ambient culture temperature (26 °C). Immunization with χ10068 primed antibody responses and specific T-cell responses to F1 and YpL (Y. pestis whole cell lysate). Oral immunization with a single dose of χ10068 provided 70% protection against a subcutaneous (s.c.) challenge with ∼ 2.6 × 10(5) LD50 of Y. pestis KIM6+ (pCD1Ap) (KIM6+Ap) and 90% protection against an intranasal (i.n.) challenge with ∼ 500 LD50 of KIM6+Ap in mice. Our results suggest that χ10068 can be used as an effective precursor to make a safe vaccine to prevent plague in humans and to eliminate plague circulation among humans and animals. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. A recombinant live attenuated tetravalent vaccine for the prevention of dengue.

    Science.gov (United States)

    Guy, Bruno; Noriega, Fernando; Ochiai, R Leon; L'azou, Maïna; Delore, Valentine; Skipetrova, Anna; Verdier, François; Coudeville, Laurent; Savarino, Stephen; Jackson, Nicholas

    2017-07-01

    Dengue is an important and still growing public health problem associated with substantial morbidity, as well as significant social and economic impact. The present review describes the main features and development of the first dengue vaccine (CYD-TDV, Dengvaxia®), which has been licensed by several dengue-endemic countries in Asia and Latin America for use in populations above 9 years of age. Areas covered: The review focuses on the large clinical development of CYD-TDV, which includes in particular two pivotal phase III efficacy trials conducted in Asia and Latin America and supported vaccine licensure. Based on these clinical data, the WHO Strategic Advisory Group of Experts (SAGE) on Immunization recommended considering introduction of the vaccine in geographic settings (national or subnational) with high burden of disease. Long-term safety follow-up studies of the efficacy trials are currently ongoing, and post-licensure studies will evaluate the vaccine effectiveness and safety in 'real-life' following vaccine introduction. Expert commentary: During vaccine development, a number of complexities were tackled, innovation pursued, and risk managed. These aspects, as well as the potential impact of CYD-TDV on public health are also discussed.

  20. Live Attenuated Recombinant Vaccine Protects Nonhuman Primates Against Ebola and Marburg Viruses

    National Research Council Canada - National Science Library

    Jones, Steven M; Feldmann, Heinz; Stroher, Ute; Geisbert, Joan B; Fernando, Lisa; Grolla, Allen; Klenk, Hans-Dieter; Sullivan, Nancy J; Volchkov, Viktor E; Fritz, Elizabeth A; Daddario, Kathleen M; Hensley, Lisa E; Jahrling, Peter B; Geisbert, Thomas W

    2005-01-01

    Vaccines and therapies are urgently needed to address public health needs stemming from emerging pathogens and biological threat agents such as the filoviruses Ebola virus (EBOV) and Marburg virus (MARV...