Language：English   Publishing type：Research paper (scientific journal)  

In general, ensuring safety is the top priority of a new modality. Although oncolytic virus armed with an immune stimulatory transgene (OVI) showed some promise, the strategic concept of simultaneously achieving maximum effectiveness and minimizing side effects has not been fully explored. We generated a variety of survivin-responsive "conditionally replicating adenoviruses that can target and treat cancer cells with multiple factors (m-CRAs)" (Surv.m-CRAs) armed with the granulocyte-macrophage colony-stimulating factor (GM-CSF) transgene downstream of various promoters using our m-CRA platform technology. We carefully analyzed both therapeutic and adverse effects of them in the in vivo syngeneic Syrian hamster cancer models. Surprisingly, an intratumor injection of a conventional OVI, which expresses the GM-CSF gene under the constitutively and strongly active "cytomegalovirus enhancer and β-actin promoter", provoked systemic and lethal GM-CSF circulation and shortened overall survival (OS). In contrast, a new conceptual type of OVI, which expressed GM-CSF under the cancer-predominant and mildly active E2F promoter or the moderately active "Rous sarcoma virus long terminal repeat", not only abolished lethal adverse events but also prolonged OS and systemic anti-cancer immunity. Our study revealed a novel concept that optimal expression levels of an immune stimulatory transgene regulated by a suitable upstream promoter is crucial for achieving high safety and maximal therapeutic effects simultaneously in OVI therapy. These results pave the way for successful development of the next-generation OVI and alert researchers about possible problems with ongoing clinical trials.

DOI： 10.1016/j.trsl.2024.07.002

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PubMed

Authorship：Lead author   Language：English   Publishing type：Research paper (scientific journal)  

AIMS: Hepatocyte growth factor (HGF) is a multifunctional cytokine that plays important roles in pancreatic physiology. Approvals of gene therapy drugs have highlighted gene therapy as an innovative new drug modality, but the very recent reports of deaths in clinical trials have provided a warning that high-dose gene therapy can cause dangerous liver toxicity. The present study aimed to develop a safe and low-dose but therapeutically effective adenovirus-mediated HGF gene therapy for streptozotocin (STZ)-induced type 1 diabetes (T1D) in mice. MAIN METHODS: A single intravenous injection of a low dose (3 × 108 plaque forming units) of adenoviral vector expressing the HGF gene under the transcriptional control of a strong promoter, i.e., the cytomegalovirus immediate-early enhancer and a modified chicken β-actin promoter (Ad.CA-HGF), was given to T1D mice. KEY FINDINGS: Low-dose HGF gene therapy significantly attenuated the elevation of blood glucose concentrations at the acute phase of T1D, and this effect persisted for several weeks. Temporal upregulation of plasma insulin at the acute phase was maintained at a normal level in Ad.CA-HGF-treated mice, suggesting that the therapeutic mechanism may involve protection of the remaining β-cells by HGF. Liver enzymes in plasma were not elevated in any of the mice, including the Ad.CA-HGF-treated animals, all of which looked healthy, suggesting the absence of lethal adverse effects observed in patients receiving high intravenous doses of viral vectors. SIGNIFICANCE: A low dose of intravenous Ad-mediated HGF gene therapy is clinically feasible and safe, and thus represents a new therapeutic strategy for treating T1D.

DOI： 10.1016/j.lfs.2020.119014

Scopus

PubMed

Language：English   Publishing type：Research paper (scientific journal)  

Human pluripotent stem cells, such as embryonic stem cells and induced pluripotent stem cells, have the potential to differentiate into a wide variety of cells in vitro and have applications in basic developmental biology research and regenerative medicine. To understand the process of differentiation from pluripotent stem cells to functional cells, it is necessary to efficiently and safely transfer and express exogenous genes. We attempted to optimize the efficient transfer of genes into pluripotent stem cells using adenoviral vectors. Comparative study of the activities of three representative ubiquitously active promoters revealed that only the CA promoter allowed robust transgene expression in human pluripotent stem cells. In addition, we established a protocol that allowed us to efficiently introduce target genes and ensure their expression even in small numbers of cells. Adenoviral vector infection of pluripotent stem cells in single-cell suspension culture yielded high gene transfer efficiency with low cytotoxicity, without losing the undifferentiated state of the pluripotent stem cells. This optimized system will facilitate developmental biology research and regenerative medicine using pluripotent stem cells.

DOI： 10.1016/j.bbrc.2021.01.009

Scopus

PubMed

Event date： 2023.5

Language：Japanese   Presentation type：Symposium, workshop panel (nominated)  

Venue：鹿児島   Country：Japan  

Event date： 2023.11

Language：Japanese  

Venue：東京   Country：Japan  

Event date： 2023.7

Presentation type：Public lecture, seminar, tutorial, course, or other speech  

Venue：京都   Country：Japan  

Event date： 2022.10

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：福岡   Country：Japan  

Event date： 2021.9

Language：English   Presentation type：Oral presentation (general)  

Country：Japan