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Sonoda-Fukuda E, Takeuchi Y, Ogawa N, Noguchi S, Takarada T, Kasahara N, Kubo S. Targeted Suicide Gene Therapy with Retroviral Replicating Vectors for Experimental Canine Cancers. Int J Mol Sci 2024; 25:2657. [PMID: 38473904 DOI: 10.3390/ijms25052657] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2024] [Revised: 02/17/2024] [Accepted: 02/22/2024] [Indexed: 03/14/2024] Open
Abstract
Cancer in dogs has increased in recent years and is a leading cause of death. We have developed a retroviral replicating vector (RRV) that specifically targets cancer cells for infection and replication. RRV carrying a suicide gene induced synchronized killing of cancer cells when administered with a prodrug after infection. In this study, we evaluated two distinct RRVs derived from amphotropic murine leukemia virus (AMLV) and gibbon ape leukemia virus (GALV) in canine tumor models both in vitro and in vivo. Despite low infection rates in normal canine cells, both RRVs efficiently infected and replicated within all the canine tumor cells tested. The efficient intratumoral spread of the RRVs after their intratumoral injection was also demonstrated in nude mouse models of subcutaneous canine tumor xenografts. When both RRVs encoded a yeast cytosine deaminase suicide gene, which converts the prodrug 5-fluorocytosine (5-FC) to the active drug 5-fluorouracil, they caused tumor-cell-specific 5-FC-induced killing of the canine tumor cells in vitro. Furthermore, in the AZACF- and AZACH-cell subcutaneous tumor xenograft models, both RRVs exerted significant antitumor effects. These results suggest that RRV-mediated suicide gene therapy is a novel therapeutic approach to canine cancers.
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Affiliation(s)
- Emiko Sonoda-Fukuda
- Laboratory of Molecular and Genetic Therapeutics, Institute of Advanced Medical Science, Hyogo Medical University, Nishinomiya 663-8501, Japan
| | - Yuya Takeuchi
- Laboratory of Molecular and Genetic Therapeutics, Institute of Advanced Medical Science, Hyogo Medical University, Nishinomiya 663-8501, Japan
- Departments of Biomedical Chemistry, School of Science and Technology, Kwansei Gakuin University, Sanda 669-1330, Japan
| | - Nao Ogawa
- Laboratory of Molecular and Genetic Therapeutics, Institute of Advanced Medical Science, Hyogo Medical University, Nishinomiya 663-8501, Japan
- Departments of Biomedical Chemistry, School of Science and Technology, Kwansei Gakuin University, Sanda 669-1330, Japan
| | - Shunsuke Noguchi
- Laboratory of Veterinary Radiology, Graduate School of Veterinary Science, Osaka Metropolitan University, Izumisano 598-8531, Japan
| | - Toru Takarada
- Laboratory of Molecular and Genetic Therapeutics, Institute of Advanced Medical Science, Hyogo Medical University, Nishinomiya 663-8501, Japan
- Laboratory of Functional Molecular Chemistry, Kobe Pharmaceutical University, Kobe 658-8558, Japan
| | - Noriyuki Kasahara
- Departments of Neurological Surgery and Radiation Oncology, University of California, San Francisco, CA 94143, USA
| | - Shuji Kubo
- Laboratory of Molecular and Genetic Therapeutics, Institute of Advanced Medical Science, Hyogo Medical University, Nishinomiya 663-8501, Japan
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Hu M, Liao X, Tao Y, Chen Y. Advances in oncolytic herpes simplex virus and adenovirus therapy for recurrent glioma. Front Immunol 2023; 14:1285113. [PMID: 38022620 PMCID: PMC10652401 DOI: 10.3389/fimmu.2023.1285113] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2023] [Accepted: 10/18/2023] [Indexed: 12/01/2023] Open
Abstract
Recurrent glioma treatment is challenging due to molecular heterogeneity and treatment resistance commonly observed in these tumors. Researchers are actively pursuing new therapeutic strategies. Oncolytic viruses have emerged as a promising option. Oncolytic viruses selectively replicate within tumor cells, destroying them and stimulating the immune system for an enhanced anticancer response. Among Oncolytic viruses investigated for recurrent gliomas, oncolytic herpes simplex virus and oncolytic adenovirus show notable potential. Genetic modifications play a crucial role in optimizing their therapeutic efficacy. Different generations of replicative conditioned oncolytic human adenovirus and oncolytic HSV have been developed, incorporating specific modifications to enhance tumor selectivity, replication efficiency, and immune activation. This review article summarizes these genetic modifications, offering insights into the underlying mechanisms of Oncolytic viruses' therapy. It also aims to identify strategies for further enhancing the therapeutic benefits of Oncolytic viruses. However, it is important to acknowledge that additional research and clinical trials are necessary to establish the safety, efficacy, and optimal utilization of Oncolytic viruses in treating recurrent glioblastoma.
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Affiliation(s)
- Mingming Hu
- Institute of Thoracic Oncology, West China Hospital, Sichuan University, Chengdu, China
- Frontiers Science Center for Disease-Related Molecular Network, West China Hospital, Sichuan University, Chengdu, China
| | - XuLiang Liao
- Institute of Thoracic Oncology, West China Hospital, Sichuan University, Chengdu, China
- Frontiers Science Center for Disease-Related Molecular Network, West China Hospital, Sichuan University, Chengdu, China
| | - Yi Tao
- Institute of Thoracic Oncology, West China Hospital, Sichuan University, Chengdu, China
- Frontiers Science Center for Disease-Related Molecular Network, West China Hospital, Sichuan University, Chengdu, China
| | - Yaohui Chen
- Institute of Thoracic Oncology, West China Hospital, Sichuan University, Chengdu, China
- Department of Thoracic Surgery, West China Hospital, Sichuan University, Chengdu, China
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Wong B, Birtch R, Rezaei R, Jamieson T, Crupi MJF, Diallo JS, Ilkow CS. Optimal delivery of RNA interference by viral vectors for cancer therapy. Mol Ther 2023; 31:3127-3145. [PMID: 37735876 PMCID: PMC10638062 DOI: 10.1016/j.ymthe.2023.09.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Revised: 08/28/2023] [Accepted: 09/14/2023] [Indexed: 09/23/2023] Open
Abstract
In recent years, there has been a surge in the innovative modification and application of the viral vector-based gene therapy field. Significant and consistent improvements in the engineering, delivery, and safety of viral vectors have set the stage for their application as RNA interference (RNAi) delivery tools. Viral vector-based delivery of RNAi has made remarkable breakthroughs in the treatment of several debilitating diseases and disorders (e.g., neurological diseases); however, their novelty has yet to be fully applied and utilized for the treatment of cancer. This review highlights the most promising and emerging viral vector delivery tools for RNAi therapeutics while discussing the variables limiting their success and suitability for cancer therapy. Specifically, we outline different integrating and non-integrating viral platforms used for gene delivery, currently employed RNAi targets for anti-cancer effect, and various strategies used to optimize the safety and efficacy of these RNAi therapeutics. Most importantly, we provide great insight into what challenges exist in their application as cancer therapeutics and how these challenges can be effectively navigated to advance the field.
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Affiliation(s)
- Boaz Wong
- Centre for Innovative Cancer Research, Ottawa Hospital Research Institute, Ottawa, ON K1H 8L6, Canada; Department of Biochemistry, Microbiology and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, ON K1H 8M5, Canada
| | - Rayanna Birtch
- Centre for Innovative Cancer Research, Ottawa Hospital Research Institute, Ottawa, ON K1H 8L6, Canada; Department of Biochemistry, Microbiology and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, ON K1H 8M5, Canada
| | - Reza Rezaei
- Centre for Innovative Cancer Research, Ottawa Hospital Research Institute, Ottawa, ON K1H 8L6, Canada; Department of Biochemistry, Microbiology and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, ON K1H 8M5, Canada
| | - Taylor Jamieson
- Centre for Innovative Cancer Research, Ottawa Hospital Research Institute, Ottawa, ON K1H 8L6, Canada; Department of Biochemistry, Microbiology and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, ON K1H 8M5, Canada
| | - Mathieu J F Crupi
- Centre for Innovative Cancer Research, Ottawa Hospital Research Institute, Ottawa, ON K1H 8L6, Canada; Department of Biochemistry, Microbiology and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, ON K1H 8M5, Canada
| | - Jean-Simon Diallo
- Centre for Innovative Cancer Research, Ottawa Hospital Research Institute, Ottawa, ON K1H 8L6, Canada; Department of Biochemistry, Microbiology and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, ON K1H 8M5, Canada
| | - Carolina S Ilkow
- Centre for Innovative Cancer Research, Ottawa Hospital Research Institute, Ottawa, ON K1H 8L6, Canada; Department of Biochemistry, Microbiology and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, ON K1H 8M5, Canada.
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Pellaers E, Bhat A, Christ F, Debyser Z. Determinants of Retroviral Integration and Implications for Gene Therapeutic MLV-Based Vectors and for a Cure for HIV-1 Infection. Viruses 2022; 15:32. [PMID: 36680071 PMCID: PMC9861059 DOI: 10.3390/v15010032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Revised: 12/14/2022] [Accepted: 12/16/2022] [Indexed: 12/24/2022] Open
Abstract
To complete their replication cycle, retroviruses need to integrate a DNA copy of their RNA genome into a host chromosome. Integration site selection is not random and is driven by multiple viral and cellular host factors specific to different classes of retroviruses. Today, overwhelming evidence from cell culture, animal experiments and clinical data suggests that integration sites are important for retroviral replication, oncogenesis and/or latency. In this review, we will summarize the increasing knowledge of the mechanisms underlying the integration site selection of the gammaretrovirus MLV and the lentivirus HIV-1. We will discuss how host factors of the integration site selection of retroviruses may steer the development of safer viral vectors for gene therapy. Next, we will discuss how altering the integration site preference of HIV-1 using small molecules could lead to a cure for HIV-1 infection.
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Affiliation(s)
| | | | | | - Zeger Debyser
- Molecular Virology and Gene Therapy, KU Leuven, Herestraat 49, 3000 Leuven, Belgium
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Qi Z, Long X, Liu J, Cheng P. Glioblastoma microenvironment and its reprogramming by oncolytic virotherapy. Front Cell Neurosci 2022; 16:819363. [PMID: 36159398 PMCID: PMC9507431 DOI: 10.3389/fncel.2022.819363] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2021] [Accepted: 08/17/2022] [Indexed: 11/13/2022] Open
Abstract
Glioblastoma (GBM), a highly aggressive form of brain tumor, responds poorly to current conventional therapies, including surgery, radiation therapy, and systemic chemotherapy. The reason is that the delicate location of the primary tumor and the existence of the blood-brain barrier limit the effectiveness of traditional local and systemic therapies. The immunosuppressive status and multiple carcinogenic pathways in the complex GBM microenvironment also pose challenges for immunotherapy and single-targeted therapy. With an improving understanding of the GBM microenvironment, it has become possible to consider the immunosuppressive and highly angiogenic GBM microenvironment as an excellent opportunity to improve the existing therapeutic efficacy. Oncolytic virus therapy can exert antitumor effects on various components of the GBM microenvironment. In this review, we have focused on the current status of oncolytic virus therapy for GBM and the related literature on antitumor mechanisms. Moreover, the limitations of oncolytic virus therapy as a monotherapy and future directions that may enhance the field have also been discussed.
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Affiliation(s)
- Zhongbing Qi
- Department of State Key Laboratory of Biotherapy and Cancer Center/Collaborative Innovation Center for Biotherapy, West China Hospital, Sichuan University, Chengdu, China
| | - Xiangyu Long
- Department of Biotherapy, Cancer Center, West China Hospital of Sichuan University, Chengdu, China
- Department of Oncology, West China Guang’an Hospital, Sichuan University, Guangan, China
| | - Jiyan Liu
- Department of Biotherapy, Cancer Center, West China Hospital of Sichuan University, Chengdu, China
- *Correspondence: Ping Cheng Jiyan Liu
| | - Ping Cheng
- Department of State Key Laboratory of Biotherapy and Cancer Center/Collaborative Innovation Center for Biotherapy, West China Hospital, Sichuan University, Chengdu, China
- *Correspondence: Ping Cheng Jiyan Liu
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Collins SA, Shah AH, Ostertag D, Kasahara N, Jolly DJ. Clinical development of retroviral replicating vector Toca 511 for gene therapy of cancer. Expert Opin Biol Ther 2021; 21:1199-1214. [PMID: 33724117 PMCID: PMC8429069 DOI: 10.1080/14712598.2021.1902982] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Accepted: 03/10/2021] [Indexed: 01/23/2023]
Abstract
INTRODUCTION The use of tumor-selectively replicating viruses is a rapidly expanding field that is showing considerable promise for cancer treatment. Retroviral replicating vectors (RRV) are unique among the various replication-competent viruses currently being investigated for potential clinical utility, because they permanently integrate into the cancer cell genome and are capable of long-term persistence within tumors. RRV can mediate efficient tumor-specific delivery of prodrug activator genes, and subsequent prodrug treatment leads to synchronized cell killing of infected cancer cells, as well as activation of antitumor immune responses. AREAS COVERED Here we review preclinical studies supporting bench-to-bedside translation of Toca 511, an optimized RRV for prodrug activator gene therapy, the results from Phase I through III clinical trials to date, and potential future directions for this therapy as well as other clinical candidate RRV. EXPERT OPINION Toca 511 has shown highly promising results in early-stage clinical trials. This vector progressed to a registrational Phase III trial, but the results announced in late 2019 appeared negative overall. However, the median prodrug dosing schedule was not optimal, and promising possible efficacy was observed in some prespecified subgroups. Further clinical investigation, as well as development of RRV with other transgene payloads, is merited.
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Affiliation(s)
- Sara A Collins
- Department of Neurological Surgery, University of California, San Francisco (UCSF), San Francisco, California, United States of America
| | - Ashish H Shah
- Department of Neurological Surgery, Miller School of Medicine, University of Miami, Florida, United States of America
| | - Derek Ostertag
- Tocagen, Inc., San Diego, California, United States of America
| | - Noriyuki Kasahara
- Department of Neurological Surgery, University of California, San Francisco (UCSF), San Francisco, California, United States of America
- Department of Radiation Oncology, University of California, San Francisco (UCSF), California, United States of America
| | - Douglas J Jolly
- Tocagen, Inc., San Diego, California, United States of America
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Stavrakaki E, Dirven CMF, Lamfers MLM. Personalizing Oncolytic Virotherapy for Glioblastoma: In Search of Biomarkers for Response. Cancers (Basel) 2021; 13:cancers13040614. [PMID: 33557101 PMCID: PMC7913874 DOI: 10.3390/cancers13040614] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2020] [Revised: 01/29/2021] [Accepted: 01/29/2021] [Indexed: 12/14/2022] Open
Abstract
Simple Summary Glioblastoma (GBM) is the most frequent and aggressive primary brain tumor. Despite multimodal treatment, the prognosis of GBM patients remains very poor. Oncolytic virotherapy is being evaluated as novel treatment for this patient group and clinical trials testing oncolytic viruses have shown impressive responses, albeit in a small subset of GBM patients. Obtaining insight into specific tumor- or patient-related characteristics of the responding patients, may in the future improve response rates. In this review we discuss factors related to oncolytic activity of the most widely applied oncolytic virus strains as well as potential biomarkers and future assays that may allow us to predict response to these agents. Such biomarkers and tools may in the future enable personalizing oncolytic virotherapy for GBM patients. Abstract Oncolytic virus (OV) treatment may offer a new treatment option for the aggressive brain tumor glioblastoma. Clinical trials testing oncolytic viruses in this patient group have shown promising results, with patients achieving impressive long-term clinical responses. However, the number of responders to each OV remains low. This is thought to arise from the large heterogeneity of these tumors, both in terms of molecular make-up and their immune-suppressive microenvironment, leading to variability in responses. An approach that may improve response rates is the personalized utilization of oncolytic viruses against Glioblastoma (GBM), based on specific tumor- or patient-related characteristics. In this review, we discuss potential biomarkers for response to different OVs as well as emerging ex vivo assays that in the future may enable selection of optimal OV for a specific patient and design of stratified clinical OV trials for GBM.
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Monie DD, Bhandarkar AR, Parney IF, Correia C, Sarkaria JN, Vile RG, Li H. Synthetic and systems biology principles in the design of programmable oncolytic virus immunotherapies for glioblastoma. Neurosurg Focus 2021; 50:E10. [PMID: 33524942 DOI: 10.3171/2020.12.focus20855] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Accepted: 12/04/2020] [Indexed: 12/11/2022]
Abstract
Oncolytic viruses (OVs) are a class of immunotherapeutic agents with promising preclinical results for the treatment of glioblastoma (GBM) but have shown limited success in recent clinical trials. Advanced bioengineering principles from disciplines such as synthetic and systems biology are needed to overcome the current challenges faced in developing effective OV-based immunotherapies for GBMs, including off-target effects and poor clinical responses. Synthetic biology is an emerging field that focuses on the development of synthetic DNA constructs that encode networks of genes and proteins (synthetic genetic circuits) to perform novel functions, whereas systems biology is an analytical framework that enables the study of complex interactions between host pathways and these synthetic genetic circuits. In this review, the authors summarize synthetic and systems biology concepts for developing programmable, logic-based OVs to treat GBMs. Programmable OVs can increase selectivity for tumor cells and enhance the local immunological response using synthetic genetic circuits. The authors discuss key principles for developing programmable OV-based immunotherapies, including how to 1) select an appropriate chassis, a vector that carries a synthetic genetic circuit, and 2) design a synthetic genetic circuit that can be programmed to sense key signals in the GBM microenvironment and trigger release of a therapeutic payload. To illustrate these principles, some original laboratory data are included, highlighting the need for systems biology studies, as well as some preliminary network analyses in preparation for synthetic biology applications. Examples from the literature of state-of-the-art synthetic genetic circuits that can be packaged into leading candidate OV chassis are also surveyed and discussed.
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Affiliation(s)
- Dileep D Monie
- Departments of1Immunology.,6Mayo Clinic Alix School of Medicine.,7Mayo Clinic Graduate School of Biomedical Sciences; and Mayo Clinic College of Medicine and Science, Rochester, Minnesota
| | | | | | - Cristina Correia
- 5Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic
| | | | | | - Hu Li
- 5Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic
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Hogan DJ, Zhu JJ, Diago OR, Gammon D, Haghighi A, Lu G, Das A, Gruber HE, Jolly DJ, Ostertag D. Molecular Analyses Support the Safety and Activity of Retroviral Replicating Vector Toca 511 in Patients. Clin Cancer Res 2018; 24:4680-4693. [DOI: 10.1158/1078-0432.ccr-18-0619] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2018] [Revised: 05/03/2018] [Accepted: 06/13/2018] [Indexed: 11/16/2022]
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Hiraoka K, Inagaki A, Kato Y, Huang TT, Mitchell LA, Kamijima S, Takahashi M, Matsumoto H, Hacke K, Kruse CA, Ostertag D, Robbins JM, Gruber HE, Jolly DJ, Kasahara N. Retroviral replicating vector-mediated gene therapy achieves long-term control of tumor recurrence and leads to durable anticancer immunity. Neuro Oncol 2018; 19:918-929. [PMID: 28387831 PMCID: PMC5574670 DOI: 10.1093/neuonc/nox038] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Background Prodrug-activator gene therapy with Toca 511, a tumor-selective retroviral replicating vector (RRV) encoding yeast cytosine deaminase, is being evaluated in recurrent high-grade glioma patients. Nonlytic retroviral infection leads to permanent integration of RRV into the cancer cell genome, converting infected cancer cell and progeny into stable vector producer cells, enabling ongoing transduction and viral persistence within tumors. Cytosine deaminase in infected tumor cells converts the antifungal prodrug 5-fluorocytosine into the anticancer drug 5-fluorouracil, mediating local tumor destruction without significant systemic adverse effects. Methods Here we investigated mechanisms underlying the therapeutic efficacy of this approach in orthotopic brain tumor models, employing both human glioma xenografts in immunodeficient hosts and syngeneic murine gliomas in immunocompetent hosts. Results In both models, a single injection of replicating vector followed by prodrug administration achieved long-term survival benefit. In the immunodeficient model, tumors recurred repeatedly, but bioluminescence imaging of tumors enabled tailored scheduling of multicycle prodrug administration, continued control of disease burden, and long-term survival. In the immunocompetent model, complete loss of tumor signal was observed after only 1-2 cycles of prodrug, followed by long-term survival without recurrence for >300 days despite discontinuation of prodrug. Long-term survivors rejected challenge with uninfected glioma cells, indicating immunological responses against native tumor antigens, and immune cell depletion showed a critical role for CD4+ T cells. Conclusion These results support dual mechanisms of action contributing to the efficacy of RRV-mediated prodrug-activator gene therapy: long-term tumor control by prodrug conversion-mediated cytoreduction, and induction of antitumor immunity.
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Affiliation(s)
- Kei Hiraoka
- Department of Medicine, University of California Los Angeles (UCLA), Los Angeles, California; Department of Cell Biology and Sylvester Comprehensive Cancer Center, Miller School of Medicine, University of Miami, Miami, Florida; Department of Molecular and Medical Pharmacology, University of California Los Angeles, Los Angeles, California; Tocagen Inc., San Diego, California; Department of Neurosurgery, University of California Los Angeles, Los Angeles, California
| | - Akihito Inagaki
- Department of Medicine, University of California Los Angeles (UCLA), Los Angeles, California; Department of Cell Biology and Sylvester Comprehensive Cancer Center, Miller School of Medicine, University of Miami, Miami, Florida; Department of Molecular and Medical Pharmacology, University of California Los Angeles, Los Angeles, California; Tocagen Inc., San Diego, California; Department of Neurosurgery, University of California Los Angeles, Los Angeles, California
| | - Yuki Kato
- Department of Medicine, University of California Los Angeles (UCLA), Los Angeles, California; Department of Cell Biology and Sylvester Comprehensive Cancer Center, Miller School of Medicine, University of Miami, Miami, Florida; Department of Molecular and Medical Pharmacology, University of California Los Angeles, Los Angeles, California; Tocagen Inc., San Diego, California; Department of Neurosurgery, University of California Los Angeles, Los Angeles, California
| | - Tiffany T Huang
- Department of Medicine, University of California Los Angeles (UCLA), Los Angeles, California; Department of Cell Biology and Sylvester Comprehensive Cancer Center, Miller School of Medicine, University of Miami, Miami, Florida; Department of Molecular and Medical Pharmacology, University of California Los Angeles, Los Angeles, California; Tocagen Inc., San Diego, California; Department of Neurosurgery, University of California Los Angeles, Los Angeles, California
| | - Leah A Mitchell
- Department of Medicine, University of California Los Angeles (UCLA), Los Angeles, California; Department of Cell Biology and Sylvester Comprehensive Cancer Center, Miller School of Medicine, University of Miami, Miami, Florida; Department of Molecular and Medical Pharmacology, University of California Los Angeles, Los Angeles, California; Tocagen Inc., San Diego, California; Department of Neurosurgery, University of California Los Angeles, Los Angeles, California
| | - Shuichi Kamijima
- Department of Medicine, University of California Los Angeles (UCLA), Los Angeles, California; Department of Cell Biology and Sylvester Comprehensive Cancer Center, Miller School of Medicine, University of Miami, Miami, Florida; Department of Molecular and Medical Pharmacology, University of California Los Angeles, Los Angeles, California; Tocagen Inc., San Diego, California; Department of Neurosurgery, University of California Los Angeles, Los Angeles, California
| | - Masamichi Takahashi
- Department of Medicine, University of California Los Angeles (UCLA), Los Angeles, California; Department of Cell Biology and Sylvester Comprehensive Cancer Center, Miller School of Medicine, University of Miami, Miami, Florida; Department of Molecular and Medical Pharmacology, University of California Los Angeles, Los Angeles, California; Tocagen Inc., San Diego, California; Department of Neurosurgery, University of California Los Angeles, Los Angeles, California
| | - Hiroshi Matsumoto
- Department of Medicine, University of California Los Angeles (UCLA), Los Angeles, California; Department of Cell Biology and Sylvester Comprehensive Cancer Center, Miller School of Medicine, University of Miami, Miami, Florida; Department of Molecular and Medical Pharmacology, University of California Los Angeles, Los Angeles, California; Tocagen Inc., San Diego, California; Department of Neurosurgery, University of California Los Angeles, Los Angeles, California
| | - Katrin Hacke
- Department of Medicine, University of California Los Angeles (UCLA), Los Angeles, California; Department of Cell Biology and Sylvester Comprehensive Cancer Center, Miller School of Medicine, University of Miami, Miami, Florida; Department of Molecular and Medical Pharmacology, University of California Los Angeles, Los Angeles, California; Tocagen Inc., San Diego, California; Department of Neurosurgery, University of California Los Angeles, Los Angeles, California
| | - Carol A Kruse
- Department of Medicine, University of California Los Angeles (UCLA), Los Angeles, California; Department of Cell Biology and Sylvester Comprehensive Cancer Center, Miller School of Medicine, University of Miami, Miami, Florida; Department of Molecular and Medical Pharmacology, University of California Los Angeles, Los Angeles, California; Tocagen Inc., San Diego, California; Department of Neurosurgery, University of California Los Angeles, Los Angeles, California
| | - Derek Ostertag
- Department of Medicine, University of California Los Angeles (UCLA), Los Angeles, California; Department of Cell Biology and Sylvester Comprehensive Cancer Center, Miller School of Medicine, University of Miami, Miami, Florida; Department of Molecular and Medical Pharmacology, University of California Los Angeles, Los Angeles, California; Tocagen Inc., San Diego, California; Department of Neurosurgery, University of California Los Angeles, Los Angeles, California
| | - Joan M Robbins
- Department of Medicine, University of California Los Angeles (UCLA), Los Angeles, California; Department of Cell Biology and Sylvester Comprehensive Cancer Center, Miller School of Medicine, University of Miami, Miami, Florida; Department of Molecular and Medical Pharmacology, University of California Los Angeles, Los Angeles, California; Tocagen Inc., San Diego, California; Department of Neurosurgery, University of California Los Angeles, Los Angeles, California
| | - Harry E Gruber
- Department of Medicine, University of California Los Angeles (UCLA), Los Angeles, California; Department of Cell Biology and Sylvester Comprehensive Cancer Center, Miller School of Medicine, University of Miami, Miami, Florida; Department of Molecular and Medical Pharmacology, University of California Los Angeles, Los Angeles, California; Tocagen Inc., San Diego, California; Department of Neurosurgery, University of California Los Angeles, Los Angeles, California
| | - Douglas J Jolly
- Department of Medicine, University of California Los Angeles (UCLA), Los Angeles, California; Department of Cell Biology and Sylvester Comprehensive Cancer Center, Miller School of Medicine, University of Miami, Miami, Florida; Department of Molecular and Medical Pharmacology, University of California Los Angeles, Los Angeles, California; Tocagen Inc., San Diego, California; Department of Neurosurgery, University of California Los Angeles, Los Angeles, California
| | - Noriyuki Kasahara
- Department of Medicine, University of California Los Angeles (UCLA), Los Angeles, California; Department of Cell Biology and Sylvester Comprehensive Cancer Center, Miller School of Medicine, University of Miami, Miami, Florida; Department of Molecular and Medical Pharmacology, University of California Los Angeles, Los Angeles, California; Tocagen Inc., San Diego, California; Department of Neurosurgery, University of California Los Angeles, Los Angeles, California
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Mitchell LA, Lopez Espinoza F, Mendoza D, Kato Y, Inagaki A, Hiraoka K, Kasahara N, Gruber HE, Jolly DJ, Robbins JM. Toca 511 gene transfer and treatment with the prodrug, 5-fluorocytosine, promotes durable antitumor immunity in a mouse glioma model. Neuro Oncol 2018; 19:930-939. [PMID: 28387849 PMCID: PMC5570153 DOI: 10.1093/neuonc/nox037] [Citation(s) in RCA: 60] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Background. Toca 511 (vocimagene amiretrorepvec) is a retroviral replicating vector encoding an optimized yeast cytosine deaminase (CD). Tumor-selective expression of CD converts the prodrug, 5-fluorocytosine (5-FC), into the active chemotherapeutic, 5-fluorouracil (5-FU). This therapeutic approach is being tested in a randomized phase II/III trial in recurrent glioblastoma and anaplastic astrocytoma (NCT0241416). The aim of this study was to identify the immune cell subsets contributing to antitumor immune responses following treatment with 5-FC in Toca 511–expressing gliomas in a syngeneic mouse model. Methods. Flow cytometry was utilized to monitor and characterize the immune cell infiltrate in subcutaneous Tu-2449 gliomas in B6C3F1 mice treated with Toca 511 and 5-FC. Results. Tumor-bearing animals treated with Toca 511 and 5-FC display alterations in immune cell populations within the tumor that result in antitumor immune protection. Attenuated immune subsets were exclusive to immunosuppressive cells of myeloid origin. Depletion of immunosuppressive cells temporally preceded a second event which included expansion of T cells which were polarized away from Th2 and Th17 in the CD4+ T cell compartment with concomitant expansion of interferon gamma–expressing CD8+ T cells. Immune alterations correlated with clearance of Tu-2449 subcutaneous tumors and T cell–dependent protection from future tumor challenge. Conclusions. Treatment with Toca 511 and 5-FC has a concentrated effect at the site of the tumor which causes direct tumor cell death and alterations in immune cell infiltrate, resulting in a tumor microenvironment that is more permissive to establishment of a T cell mediated antitumor immune response.
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Affiliation(s)
- Leah A Mitchell
- Tocagen Inc., San Diego, California; DNAtrix Inc., Houston, Texas; University of California Los Angeles, Los Angeles, California; Department of Gastroenterological Surgery, Hokkaido University, Sapporo, Japan; Department of Cell Biology and Sylvester Comprehensive Cancer Center, Miller School of Medicine, University of Miami, Miami, Florida
| | - Fernando Lopez Espinoza
- Tocagen Inc., San Diego, California; DNAtrix Inc., Houston, Texas; University of California Los Angeles, Los Angeles, California; Department of Gastroenterological Surgery, Hokkaido University, Sapporo, Japan; Department of Cell Biology and Sylvester Comprehensive Cancer Center, Miller School of Medicine, University of Miami, Miami, Florida
| | - Daniel Mendoza
- Tocagen Inc., San Diego, California; DNAtrix Inc., Houston, Texas; University of California Los Angeles, Los Angeles, California; Department of Gastroenterological Surgery, Hokkaido University, Sapporo, Japan; Department of Cell Biology and Sylvester Comprehensive Cancer Center, Miller School of Medicine, University of Miami, Miami, Florida
| | - Yuki Kato
- Tocagen Inc., San Diego, California; DNAtrix Inc., Houston, Texas; University of California Los Angeles, Los Angeles, California; Department of Gastroenterological Surgery, Hokkaido University, Sapporo, Japan; Department of Cell Biology and Sylvester Comprehensive Cancer Center, Miller School of Medicine, University of Miami, Miami, Florida
| | - Akihito Inagaki
- Tocagen Inc., San Diego, California; DNAtrix Inc., Houston, Texas; University of California Los Angeles, Los Angeles, California; Department of Gastroenterological Surgery, Hokkaido University, Sapporo, Japan; Department of Cell Biology and Sylvester Comprehensive Cancer Center, Miller School of Medicine, University of Miami, Miami, Florida
| | - Kei Hiraoka
- Tocagen Inc., San Diego, California; DNAtrix Inc., Houston, Texas; University of California Los Angeles, Los Angeles, California; Department of Gastroenterological Surgery, Hokkaido University, Sapporo, Japan; Department of Cell Biology and Sylvester Comprehensive Cancer Center, Miller School of Medicine, University of Miami, Miami, Florida
| | - Noriyuki Kasahara
- Tocagen Inc., San Diego, California; DNAtrix Inc., Houston, Texas; University of California Los Angeles, Los Angeles, California; Department of Gastroenterological Surgery, Hokkaido University, Sapporo, Japan; Department of Cell Biology and Sylvester Comprehensive Cancer Center, Miller School of Medicine, University of Miami, Miami, Florida
| | - Harry E Gruber
- Tocagen Inc., San Diego, California; DNAtrix Inc., Houston, Texas; University of California Los Angeles, Los Angeles, California; Department of Gastroenterological Surgery, Hokkaido University, Sapporo, Japan; Department of Cell Biology and Sylvester Comprehensive Cancer Center, Miller School of Medicine, University of Miami, Miami, Florida
| | - Douglas J Jolly
- Tocagen Inc., San Diego, California; DNAtrix Inc., Houston, Texas; University of California Los Angeles, Los Angeles, California; Department of Gastroenterological Surgery, Hokkaido University, Sapporo, Japan; Department of Cell Biology and Sylvester Comprehensive Cancer Center, Miller School of Medicine, University of Miami, Miami, Florida
| | - Joan M Robbins
- Tocagen Inc., San Diego, California; DNAtrix Inc., Houston, Texas; University of California Los Angeles, Los Angeles, California; Department of Gastroenterological Surgery, Hokkaido University, Sapporo, Japan; Department of Cell Biology and Sylvester Comprehensive Cancer Center, Miller School of Medicine, University of Miami, Miami, Florida
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12
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Lundstrom K. New frontiers in oncolytic viruses: optimizing and selecting for virus strains with improved efficacy. Biologics 2018; 12:43-60. [PMID: 29445265 PMCID: PMC5810530 DOI: 10.2147/btt.s140114] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Oncolytic viruses have demonstrated selective replication and killing of tumor cells. Different types of oncolytic viruses – adenoviruses, alphaviruses, herpes simplex viruses, Newcastle disease viruses, rhabdoviruses, Coxsackie viruses, and vaccinia viruses – have been applied as either naturally occurring or engineered vectors. Numerous studies in animal-tumor models have demonstrated substantial tumor regression and prolonged survival rates. Moreover, clinical trials have confirmed good safety profiles and therapeutic efficacy for oncolytic viruses. Most encouragingly, the first cancer gene-therapy drug – Gendicine, based on oncolytic adenovirus type 5 – was approved in China. Likewise, a second-generation oncolytic herpes simplex virus-based drug for the treatment of melanoma has been registered in the US and Europe as talimogene laherparepvec.
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13
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Howells A, Marelli G, Lemoine NR, Wang Y. Oncolytic Viruses-Interaction of Virus and Tumor Cells in the Battle to Eliminate Cancer. Front Oncol 2017; 7:195. [PMID: 28944214 PMCID: PMC5596080 DOI: 10.3389/fonc.2017.00195] [Citation(s) in RCA: 87] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2017] [Accepted: 08/15/2017] [Indexed: 12/13/2022] Open
Abstract
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.
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Affiliation(s)
- Anwen Howells
- Centre for Molecular Oncology, Barts Cancer Institute, Queen Mary University of London, London, United Kingdom
| | - Giulia Marelli
- Centre for Molecular Oncology, Barts Cancer Institute, Queen Mary University of London, London, United Kingdom
| | - Nicholas R Lemoine
- Centre for Molecular Oncology, Barts Cancer Institute, Queen Mary University of London, London, United Kingdom.,National Centre for International Research in Cell and Gene Therapy, Sino-British Research Centre for Molecular Oncology, Academy of Medical Sciences, Zhengzhou University, Zhengzhou, China
| | - Yaohe Wang
- Centre for Molecular Oncology, Barts Cancer Institute, Queen Mary University of London, London, United Kingdom.,National Centre for International Research in Cell and Gene Therapy, Sino-British Research Centre for Molecular Oncology, Academy of Medical Sciences, Zhengzhou University, Zhengzhou, China
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14
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Shneor D, Folberg R, Pe'er J, Honigman A, Frenkel S. Stable knockdown of CREB, HIF-1 and HIF-2 by replication-competent retroviruses abrogates the responses to hypoxia in hepatocellular carcinoma. Cancer Gene Ther 2016; 24:64-74. [PMID: 27934882 PMCID: PMC5339434 DOI: 10.1038/cgt.2016.68] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2016] [Revised: 09/05/2016] [Accepted: 09/07/2016] [Indexed: 12/19/2022]
Abstract
The fast proliferation of tumor cells develops faster than the vasculature, resulting, in most malignant tumors, in generation of hypoxic regions. Hypoxia renders solid tumors resistant to radiation and chemotherapeutics while providing opportunities for tumor-selective therapies targeting tumor hypoxia. Here we exploit two properties of tumors: propagation of tumor cells and ongoing generation of hypoxic regions to construct a system that preferentially leads to the death of tumor cells and thus hinders tumor growth. We constructed murine leukemia virus replication-competent (RCR) viruses that infect only propagating cells. These viruses express small hairpin RNAs (shRNAs) targeting cyclic AMP-response-element binding protein (CREB), hypoxia-inducible factors 1 (HIF)-1 or HIF-2 individually or all three together (X3). These viruses efficiently infected in vitro human hepatocellular carcinoma (HepG2 and FLC4) cells and established persistence of the virus and knocked down the expression of the regulators of the hypoxia-responding genes. Knockdown of either HIF-1 or CREB or both in hypoxia reduced the expression of hypoxia-response elements- and CRE-mediated gene expression, diminished cell proliferation and increased caspase-3 activity. We did not detect any significant effect of the efficiently knocked down HIF-2 on any of the functions tested in vitro. Moreover, severe combined immunodeficiency mice implanted subcutaneously with HepG2 stably infected with recombinant RCRs showed reduction of tumor growth and vascular endothelial growth factor expression, and no hypoxia-guided neovascularization. Combined treatment (RCRs+doxorubicin) improved efficacy in the context of in vitro hypoxia and in vivo (with either vACE-CREB or vACE-X3). This synergistic effect may lead to an improved efficacy and safety profile of the treatment that may result in fewer side effects.
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Affiliation(s)
- D Shneor
- Department of Biochemistry and Molecular Biology, IMRIC, The Hebrew University-Hadassah Medical School, Jerusalem, Israel.,Department of Ophthalmology, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
| | - R Folberg
- Departments of Pathology, Ophthalmology and Biomedical Sciences, Oakland University William Beaumont School of Medicine, Rochester, MI, USA
| | - J Pe'er
- Department of Ophthalmology, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
| | - A Honigman
- Department of Biochemistry and Molecular Biology, IMRIC, The Hebrew University-Hadassah Medical School, Jerusalem, Israel.,Department of Biotechnology, Hadassah Academic College, Jerusalem, Israel
| | - S Frenkel
- Department of Ophthalmology, Hadassah-Hebrew University Medical Center, Jerusalem, Israel
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15
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Takahashi M, Valdes G, Hiraoka K, Inagaki A, Kamijima S, Micewicz E, Gruber HE, Robbins JM, Jolly DJ, McBride WH, Iwamoto KS, Kasahara N. Radiosensitization of gliomas by intracellular generation of 5-fluorouracil potentiates prodrug activator gene therapy with a retroviral replicating vector. Cancer Gene Ther 2014; 21:405-410. [PMID: 25301172 PMCID: PMC4246057 DOI: 10.1038/cgt.2014.38] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2014] [Revised: 06/17/2014] [Accepted: 06/17/2014] [Indexed: 12/28/2022]
Abstract
A tumor-selective non-lytic retroviral replicating vector (RRV), Toca 511, and an extended-release formulation of 5-fluorocytosine (5-FC), Toca FC, are currently being evaluated in clinical trials in patients with recurrent high-grade glioma (NCT01156584, NCT01470794 and NCT01985256). Tumor-selective propagation of this RRV enables highly efficient transduction of glioma cells with cytosine deaminase (CD), which serves as a prodrug activator for conversion of the anti-fungal prodrug 5-FC to the anti-cancer drug 5-fluorouracil (5-FU) directly within the infected cells. We investigated whether, in addition to its direct cytotoxic effects, 5-FU generated intracellularly by RRV-mediated CD/5-FC prodrug activator gene therapy could also act as a radiosensitizing agent. Efficient transduction by RRV and expression of CD were confirmed in the highly aggressive, radioresistant human glioblastoma cell line U87EGFRvIII and its parental cell line U87MG (U87). RRV-transduced cells showed significant radiosensitization even after transient exposure to 5-FC. This was confirmed both in vitro by a clonogenic colony survival assay and in vivo by bioluminescence imaging analysis. These results provide a convincing rationale for development of tumor-targeted radiosensitization strategies utilizing the tumor-selective replicative capability of RRV, and incorporation of radiation therapy into future clinical trials evaluating Toca 511 and Toca FC in brain tumor patients.
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Affiliation(s)
- Masamichi Takahashi
- Department of Medicine, University of California Los Angeles (UCLA), Los Angeles, California, USA
| | - Gilmer Valdes
- Department of Radiation Oncology, University of California Los Angeles (UCLA), Los Angeles, California, USA
| | - Kei Hiraoka
- Department of Medicine, University of California Los Angeles (UCLA), Los Angeles, California, USA
| | - Akihito Inagaki
- Department of Medicine, University of California Los Angeles (UCLA), Los Angeles, California, USA
| | - Shuichi Kamijima
- Department of Medicine, University of California Los Angeles (UCLA), Los Angeles, California, USA
| | - Ewa Micewicz
- Department of Radiation Oncology, University of California Los Angeles (UCLA), Los Angeles, California, USA
| | | | | | | | - William H McBride
- Department of Radiation Oncology, University of California Los Angeles (UCLA), Los Angeles, California, USA
| | - Keisuke S Iwamoto
- Department of Radiation Oncology, University of California Los Angeles (UCLA), Los Angeles, California, USA
| | - Noriyuki Kasahara
- Department of Medicine, University of California Los Angeles (UCLA), Los Angeles, California, USA
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16
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Hickey MJ, Kasahara N, Mueller BM, Kruse CA. Combining cellular and gene therapy approaches for treatment of intracranial tumors. Oncoimmunology 2013; 2:e25989. [PMID: 24244896 PMCID: PMC3825732 DOI: 10.4161/onci.25989] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2013] [Accepted: 07/31/2013] [Indexed: 11/21/2022] Open
Abstract
New treatments are needed for brain metastasis, which is associated with high morbidity and mortality. Two novel cellular and gene therapy modalities were evaluated in xenograft models for human breast cancer. The individual and especially the combined treatments with alloreactive cytotoxic T lymphocytes and replicating retroviral vectors coding for prodrug activating enzymes followed later with nontoxic prodrug demonstrated efficacy without off-target effects.
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Affiliation(s)
- Michelle J Hickey
- Department of Neurosurgery; University of California Los Angeles; Los Angeles, CA USA
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17
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Lam P, Khan G, Stripecke R, Hui KM, Kasahara N, Peng KW, Guinn BA. The innovative evolution of cancer gene and cellular therapies. Cancer Gene Ther 2013; 20:141-9. [PMID: 23370333 DOI: 10.1038/cgt.2012.93] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
We provide an overview of the latest developments in cancer gene therapy--from the bench to early-stage clinical trials. We describe the most recent work of worldwide teams including experienced scientists and clinicians, reflecting the recent emergence of gene therapy from the 'Valley of Death'. The treatment efficacy of clinical gene therapy has now been shown in a number of diseases including cancer and we are observing a renewed interest by big pharmaceutical and biotechnology companies most obviously demonstrated by Amgen's acquisition of Biovex for up to USD$1 billion. There is an opportunity to be cautiously hopeful regarding the future of gene therapy in the clinic and we review here some of the most recent progress in the field.
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Affiliation(s)
- P Lam
- Division of Cellular and Molecular Research, National Cancer Centre, Singapore, Singapore
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