Novel group C oncolytic adenoviruses carrying a microRNA inhibitor demonstrate enhanced oncolytic activity in vitro and in vivo

Abstract Arming oncolytic adenoviruses with therapeutic transgenes is a well-established strategy for multimodal tumour attack. However, this strategy sometimes leads to unexpected attenuated viral replication and a loss of oncolytic effects, preventing these viruses from reaching the clinic. Previous work has shown that altering codon usage in viral genes can hamper viral fitness. Here, we have analysed how transgene codon usage impacts viral replication and oncolytic activity. We observe that, although transgenes with optimized codons show high expression levels at the first round of infection, they impair viral fitness and are therefore not expressed in a sustained manner. Conversely, transgenes encoded by suboptimal codons do not compromise viral replication and are thus stably expressed over time, allowing a greater oncolytic activity both in vitro and in vivo. Altogether, our work shows that fine-tuning codon usage leads to a concerted optimization of transgene expression and viral replication paving the way for the rational design of more efficacious oncolytic therapies.

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Transgene codon usage drives viral fitness and therapeutic efficacy in oncolytic adenoviruses

10.1101/2020.06.19.161026 ◽

2020 ◽

Author(s):

Estela Núñez-Manchón ◽

Martí Farrera-Sal ◽

Giancarlo Castellano ◽

David Medel ◽

Ramon Alemany ◽

...

Keyword(s):

Viral Replication ◽

Codon Usage ◽

Transgene Expression ◽

Rational Design ◽

Viral Fitness ◽

Fine Tuning ◽

Oncolytic Adenoviruses ◽

Oncolytic Activity

AbstractArming oncolytic adenoviruses with therapeutic transgenes is a well-established strategy for multimodal tumour attack. However, this strategy sometimes leads to unexpected attenuated viral replication and a loss of oncolytic effects, preventing these viruses from reaching the clinic. Previous work has shown that altering codon usage in viral genes can hamper viral fitness. Here, we have analysed how transgene codon usage impacts viral replication and oncolytic activity. We observe that, although transgenes with optimised codons show high expression levels at a first round of infection, they impair viral fitness and are therefore not expressed in a sustained manner. Conversely, transgenes encoded by suboptimal codons do not compromise viral replication and are thus stably expressed over time allowing a greater oncolytic activity both in vitro and in vivo. Altogether, our work shows that fine-tuning codon usage leads to a concerted optimisation of transgene expression and viral replication paving the way for the rational design of more efficacious oncolytic therapies.

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PARP inhibitor olaparib increases the oncolytic activity of dl922-947 in in vitro and in vivo model of anaplastic thyroid carcinoma

Molecular Oncology ◽

10.1016/j.molonc.2014.07.022 ◽

2014 ◽

Vol 9 (1) ◽

pp. 78-92 ◽

Cited By ~ 17

Author(s):

Carmela Passaro ◽

Massimiliano Volpe ◽

Ginevra Botta ◽

Eloise Scamardella ◽

Giuseppe Perruolo ◽

...

Keyword(s):

Thyroid Carcinoma ◽

Parp Inhibitor ◽

Anaplastic Thyroid Carcinoma ◽

In Vivo Model ◽

Oncolytic Activity

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AVIDIO as a novel oncolytic immunotherapy platform for the treatment of colorectal cancer.

Journal of Clinical Oncology ◽

10.1200/jco.2020.38.15_suppl.e15210 ◽

2020 ◽

Vol 38 (15_suppl) ◽

pp. e15210-e15210

Author(s):

Bijan Almassian ◽

Bhaskara R Madina ◽

Ju Chen ◽

Xiaoyang Ye ◽

Marie M Krady ◽

...

Keyword(s):

Colorectal Cancer ◽

T Cells ◽

Tumor Growth ◽

Semliki Forest Virus ◽

Tumor Model ◽

Oncolytic Viruses ◽

Immunomodulatory Agents ◽

Oncolytic Activity

e15210 Background: Colorectal cancer is the third deadliest of all cancers causing more than 50,000 deaths per year in the U.S. Oncolytic viruses have seen limited use for the treatment of cancers, and further improvement of these methods with immune-modulating activities may prove crucial for the effectiveness of these agents in the treatment of human malignancies. To this end, we developed an artificial virus for infectious diseases and immuno-oncology (AVIDIO) platform that employs virus-like vesicles (VLV) for both the delivery of immunomodulatory agents to tumors and oncolytic activity. Methods: The AVIDIO platform is comprised of in vitro evolved RNA-dependent RNA polymerase from an alphavirus, Semliki forest virus, and envelope glycoproteins from vesicular stomatitis virus, which together form VLVs. Both unarmed VLVs and VLVs armed with the p35 subunit of IL-12 (VLV-IL12p35), an immunomodulatory cytokine that can induce Th1-mediated immunity, were tested for oncolytic activity against various cancer cell lines, including MC38 colorectal cancer cells, in vitro. Using the MC38 syngeneic murine tumor model, we evaluated the antitumor activity of VLV-IL-12p35 in vivo. We used tumor growth measurements and analyses of tumor-infiltrating cells after consecutive treatments with VLV-IL-12p35 to monitor its antitumor and immunomodulatory activities, respectively. Results: VLV-IL-12p35 showed robust oncolytic activity against MC38 cells in vitro, killing over 80% of cells within 24 h. Treatment of intradermal MC38 tumors by intra-tumoral delivery of VLV-IL-12p35 resulted in more than 65% suppression of tumor growth within 2 weeks ( p< 0.05). VLV-IL-12p35-treated tumors also harbored significantly more CD8+ T cells, IFN-gamma-producing CD4+ T cells, and reduced numbers of Foxp3+ regulatory T cells. Conclusions: Our results show that VLV-IL-12p35 derived from the AVIDIO platform has oncolytic activity in vitro and antitumor and immunomodulatory activities in vivo. Therefore, AVIDIO is a promising platform for the delivery of immunomodulatory agents to tumors. Further optimization of the platform, including the addition of other immunomodulatory agents, is in progress to advance the AVIDIO platform to clinical applications for colorectal cancer.

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In Vitro and In Vivo Characterization of MicroRNA-Targeted Alphavirus Replicon and Helper RNAs

Journal of Virology ◽

10.1128/jvi.00310-10 ◽

2010 ◽

Vol 84 (15) ◽

pp. 7713-7725 ◽

Cited By ~ 18

Author(s):

Kurt I. Kamrud ◽

V. McNeil Coffield ◽

Gary Owens ◽

Christin Goodman ◽

Kim Alterson ◽

...

Keyword(s):

Vaccine Development ◽

Rna Replication ◽

Structural Proteins ◽

Expression Vectors ◽

Cellular Mirnas ◽

Rna Regulation ◽

Oncolytic Adenoviruses ◽

Vector Systems

ABSTRACT Alphavirus-based replicon vector systems (family Togaviridae) have been developed as expression vectors with demonstrated potential in vaccine development against both infectious diseases and cancer. The single-cycle nature of virus-like replicon particles (VRP), generated by supplying the structural proteins from separate replicable helper RNAs, is an attractive safety component of these systems. MicroRNAs (miRNAs) have emerged as important cellular RNA regulation elements. Recently, miRNAs have been employed as a mechanism to attenuate or restrict cellular tropism of replication-competent viruses, such as oncolytic adenoviruses, vesicular stomatitis virus, and picornaviruses as well as nonreplicating lentiviral and adenoviral vectors. Here, we describe the incorporation of miRNA-specific target sequences into replicable alphavirus helper RNAs that are used in trans to provide the structural proteins required for VRP production. VRP were found to be efficiently produced using miRNA-targeted helper RNAs if miRNA-specific inhibitors were introduced into cells during VRP production. In the absence of such inhibitors, cellular miRNAs were capable of downregulating helper RNA replication in vitro. When miRNA targets were incorporated into a replicon RNA, cellular miRNAs were capable of downregulating replicon RNA replication upon delivery of VRP into animals, demonstrating activity in vivo. These data provide the first example of miRNA-specific repression of alphavirus replicon and helper RNA replication and demonstrate the feasibility of miRNA targeting of expression vector helper functions that are provided in trans.

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TMOD-16. A NOVEL ADENOVIRAL-PERMISSIVE, IMMUNOCOMPETENT HAMSTER GLIOMA MODEL TO EVALUATE ONCOLYTIC ADENOVIRAL THERAPY

Neuro-Oncology ◽

10.1093/neuonc/noaa215.967 ◽

2020 ◽

Vol 22 (Supplement_2) ◽

pp. ii231-ii231

Author(s):

Lynette Phillips ◽

Joy Gumin ◽

Shoudong Li ◽

Marc Daou ◽

Daniel Ledbetter ◽

...

Keyword(s):

Immune Response ◽

Viral Replication ◽

Tumor Infiltrating Lymphocytes ◽

Peripheral Blood Lymphocytes ◽

T Antigen ◽

Sv40 Large T Antigen ◽

Oncolytic Adenoviruses ◽

Glioma Model

Abstract Oncolytic adenoviruses, including Delta-24-RGD, target tumors by direct tumor cell oncolysis and by activation of an anti-tumor immune response. Due to the species selectivity of oncolytic adenoviruses, there is currently no single preclinical animal model of glioma that supports viral replication, tumor oncolysis, and virus-mediated immune responses. To address this gap, we took advantage of the Syrian hamster to develop the first glioma model that is both adenovirus replication-permissive and immunocompetent. Hamster glioma stem-like cells (GSCs), transformed by forced expression of hTERT, SV40 large T antigen, and h-RasV12, reproducibly form intracranial tumors in hamsters. In vitro, electron microscopy and cytopathic effect assays demonstrated that hamster GSCs supported viral replication and were susceptible to Delta-24-RGD-mediated cell death. In vivo, hamster GSCs consistently developed into highly proliferative tumors resembling high-grade gliomas. Following intratumoral delivery of Delta-24-RGD, immunohistochemistry for viral proteins demonstrated viral infectivity and replication in hamster gliomas. Flow cytometry revealed increased T cell infiltration in Delta-24-RGD-infected tumors. Delta-24-RGD treatment of tumor-bearing hamsters led to significantly increased survival compared with hamsters treated with PBS. Using this model, we evaluated the effects of corticosteroid-mediated immunosuppression on Delta-24-RGD efficacy. Dexamethasone treatment significantly decreased peripheral blood lymphocytes, decreased tumor-infiltrating lymphocytes, and suppressed the levels of serum anti-adenovirus antibodies. Dexamethasone reduced the number of long-term survivors and decreased the median survival (50 days for Delta-24-RGD + dexamethasone vs undetermined for Delta-24-RGD alone). In summary, we have developed the first adenovirus-permissive, immunocompetent hamster glioma model, addressing a critical need for a model in which to study the role of direct oncolysis in driving immune mediated viral clearance versus driving an antiglioma immune response. Understanding these mechanisms is critical to optimizing the success of oncolytic adenoviral therapy in the clinic.

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Nectin-1 Expression Correlates with the Susceptibility of Malignant Melanoma to Oncolytic Herpes Simplex Virus In Vitro and In Vivo

Cancers ◽

10.3390/cancers13123058 ◽

2021 ◽

Vol 13 (12) ◽

pp. 3058

Author(s):

Barbara Schwertner ◽

Georg Lindner ◽

Camila Toledo Toledo Stauner ◽

Elisa Klapproth ◽

Clara Magnus ◽

...

Keyword(s):

Herpes Simplex Virus ◽

Herpes Simplex ◽

Intralesional Injection ◽

Surface Receptors ◽

Oncolytic Herpes Simplex Virus ◽

Simplex Virus ◽

Oncolytic Activity

Talimogene laherparepvec (T-VEC), an oncolytic herpes simplex virus, is approved for intralesional injection of unresectable stage IIIB/IVM1a melanoma. However, it is still unclear which parameter(s) predict treatment response or failure. Our study aimed at characterizing surface receptors Nectin-1 and the herpes virus entry mediator (HVEM) in addition to intracellular molecules cyclic GMP-AMP synthase (cGAS) and stimulator of interferon genes (STING) as potential bio-markers for oncolytic virus treatment. In 20 melanoma cell lines, oncolytic activity of T-VEC was correlated with the expression of Nectin-1 but not HVEM, as evaluated via flow cytometry and immunohistochemistry. Knockout using CRISPR/Cas9 technology confirmed the superior role of Nectin-1 over HVEM for entry and oncolytic activity of T-VEC. Neither cGAS nor STING as evaluated by Western Blot and immunohistochemistry correlated with T-VEC induced oncolysis. The role of these biomarkers was retrospectively analyzed for the response of 35 cutaneous melanoma metastases of 21 patients to intralesional T-VEC injection, with 21 (60.0%) of these lesions responding with complete (n = 16) or partial regression (n = 5). Nectin-1 expression in pretreatment biopsies significantly predicted treatment outcome, while the expression of HVEM, cGAS, and STING was not prognostic. Altogether, Nectin-1 served as biomarker for T-VEC-induced melanoma regression in vitro and in vivo.

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Interaction of Measles Virus Vectors with Auger Electron Emitting Radioisotopes.

Blood ◽

10.1182/blood.v106.11.5525.5525 ◽

2005 ◽

Vol 106 (11) ◽

pp. 5525-5525

Author(s):

David Dingli ◽

Kah-Whye Peng ◽

Mary E. Harvey ◽

Sompong Vongpunsawad ◽

Elizabeth R. Bergert ◽

...

Keyword(s):

Measles Virus ◽

Auger Electron ◽

Viral Vectors ◽

Soluble Form ◽

Sodium Iodide Symporter ◽

Experimental Conditions ◽

Oncolytic Activity

Abstract Background: Viral vectors based on the Edmonston strain of measles virus (MV-Edm) selectively destroy all tumor cell lines tested in vitro. The oncolytic activity of the virus is enhanced by expression of the thyroidal sodium iodide symporter (MV-NIS) that allows selective 131I uptake by infected tumor cells and eliminates myeloma tumor xenografts that are resistant to the parent virus. MV-NIS is being considered for therapy of patients with relapsed or refractory multiple myeloma. Advanced myeloma is associated with significant immunosuppression with the potential risk of uncontrolled virus proliferation. The number of agents with activity against MV is limited. Low energy (Auger) electrons have a short path length and selectively damage cells in which the isotope decays. Thus, we hypothesized that the Auger electron emitting isotope 125I, selectively taken up by cells expressing NIS, can be used to control viral proliferation. Methods: A replication competent MV that expressed both a soluble form of carcinoembryonic antigen (CEA) and NIS (MV-NICE) was rescued and characterized. Cells were infected with MV-NICE or control vectors and exposed to 125I with appropriate controls. CEA expression and viral titers were determined at different time points. The role of free radical generation on virus replication was explored. In vivo control of MV-NICE replication with 125I was attempted. Results: MV-NICE replication in vitro is inhibited by the selective uptake of 125I by cells expressing NIS. Extracellular decay of the isotope has no effect on virus proliferation. Auger electron damage is in part mediated by free radicals and abrogated by glutathione. In myeloma xenografts, control of MV-NICE with 125I was not possible under the conditions of the experiment. Conclusion: MV-NICE does not replicate faster in the presence of radiation under our experimental conditions. Auger electron emitting isotopes effectively stop propagation of MV vectors expressing NIS in vitro. Additional work is necessary to translate these observations in vivo.

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