記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Translational Research  

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

Scopus

PubMed

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Translational Medicine  

Background: Effective methods for eradicating cancer stem cells (CSCs), which are highly tumorigenic and resistant to conventional therapies, are urgently needed. Our previous studies demonstrated that survivin-responsive conditionally replicating adenoviruses regulated with multiple factors (Surv.m-CRAs), which selectively replicate in and kill a broad range of cancer-cell types, are promising anticancer agents. Here we examined the therapeutic potentials of a Surv.m-CRA against rhabdomyosarcoma stem cells (RSCs), in order to assess its clinical effectiveness and usefulness.Methods: Our previous study demonstrated that fibroblast growth factor receptor 3 (FGFR3) is a marker of RSCs. We examined survivin mRNA levels, survivin promoter activities, relative cytotoxicities of Surv.m-CRA in RSC-enriched (serum-minus) vs. RSC-exiguous (serum-plus) and FGFR3-positive vs. FGFR3-negative sorted rhabdomyosarcoma cells, and the in vivo therapeutic effects of Surv.m-CRAs on subcutaneous tumors in mice.Results: Both survivin mRNA levels and survivin promoter activities were significantly elevated under RSC-enriched relative to RSC-exiguous culture conditions, and the elevation was more prominent in FGFR3-positive vs. FGFR3-negative sorted cells than in RSC-enriched vs. RSC-exiguous conditions. Although Surv.m-CRA efficiently replicated and potently induced cell death in all populations of rhabdomyosarcoma cells, the cytotoxic effects were more pronounced in RSC-enriched or RSC-purified cells than in RSC-exiguous or progeny-purified cells. Injections of Surv.m-CRAs into tumor nodules generated by transplanting RSC-enriched cells induced significant death of rhabdomyosarcoma cells and regression of tumor nodules.Conclusions: The unique therapeutic features of Surv.m-CRA, i.e., not only its therapeutic effectiveness against all cell populations but also its increased effectiveness against CSCs, suggest that Surv.m-CRA is promising anticancer agent. © 2014 Tanoue et al.; licensee BioMed Central Ltd.

DOI： 10.1186/1479-5876-12-27

担当区分：筆頭著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Biochemical and Biophysical Research Communications  

Human pluripotent stem cells, such as embryonic stem cells (hESCs) and induced pluripotent stem cells (hiPSCs), have the ability to differentiate into various cell types, and will become a potential source of cellular materials for regenerative medicine. To make full use of hESCs or hiPSCs for both basic and clinical research, genetic modification, especially gene targeting via homologous recombination (HR), would be an essential technique. This report describes the successful gene targeting of the hypoxanthine phosphoribosyl transferase 1 (HPRT1) and the NANOG loci in human pluripotent stem cells with adeno-associated virus (AAV) vectors. At the HPRT1 locus, up to 1% of stable transformants were targeted via HR with an AAV-HPRT1 targeting vector, without loss of pluripotency. On the other hand, 20-87% of stable transformants were targeted using an AAV-NANOG-targeting vector designed for the promoter-trap strategy. In the KhES-3 cell line, which shows particularly high fragility to experimental manipulation, gene targeting was successful only by using an AAV vector but not by electroporation. In addition to hESC, gene targeting was achieved in hiPSC lines at similar frequencies. These data indicate that AAV vectors may therefore be a useful tool to introduce genetic modifications in hESCs and hiPSCs. © 2009 Elsevier Inc. All rights reserved.

DOI： 10.1016/j.bbrc.2009.08.075

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Zebrafish  

Viral vectors represent a tractable system that can efficiently introduce an exogenous gene into different target cells and are thus a potentially powerful genetic manipulation tool. In our current study, we investigated the infection efficiency of mammalian virus vectors, adenoviruses (Ads), adeno-associated viruses, and lentiviruses to the Sertoli cell line and the newly established cell line from a single embryo in zebrafish. Among the viral vectors tested, Ads showed the highest infection efficiency of 10 7-108 green fluorescent protein-transducing units (gtu)/mL in zebrafish cells. In addition, the adenoviral vector was also infected at 105 gtu/mL in the medaka testicular somatic cell line that was established from the testes of p53-deficient mutant. Further, we found that Ads could successfully infect cultured male zebrafish germ cells. Our results thus indicate that the adenoviral vector could be used as a chromosomally nonintegrating vector system in zebrafish. © Copyright 2009, Mary Ann Liebert, Inc. 2009.

DOI： 10.1089/zeb.2009.0596

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Proceedings of the National Academy of Sciences of the United States of America  

Human embryonic stem (hES) cells are regarded as a potentially unlimited source of cellular materials for regenerative medicine. For biological studies and clinical applications using primate ES cells, the development of a general strategy to obtain efficient gene delivery and genetic manipulation, especially gene targeting via homologous recombination (HR), would be of paramount importance. However, unlike mouse ES (mES) cells, efficient strategies for transient gene delivery and HR in hES cells have not been established. Here, we report that helper-dependent adenoviral vectors (HDAdVs) were able to transfer genes in hES and cynomolgus monkey (Macaca fasicularis) ES (cES) cells efficiently. Without losing the undifferentiated state of the ES cells, transient gene transfer efficiency was ≈100%. Using HDAdVs with homology arms, approximately one out of 10 chromosomal integrations of the vector was via HR, whereas the rate was only ≈1% with other gene delivery methods. Furthermore, in combination with negative selection, ≈45% of chromosomal integrations of the vector were targeted integrations, indicating that HDAdVs would be a powerful tool for genetic manipulation in hES cells and potentially in other types of human stem cells, such as induced pluripotent stem (iPS) cells. © 2008 by The National Academy of Sciences of the USA.

DOI： 10.1073/pnas.0806976105

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Phycology  

We investigated the phylogenetic relationships and the taxonomy of 20 sarcinoid strains by their morphological features and using 18S rDNA sequence data. Nineteen strains of Chlorosarcinopsis (Gerneck) Herndon and allied genera were divided into four groups (A-D). Group A, comprising eight species, was concordant with the description of Chlorosarcinopsis and divided into four polyphyletic subgroups. Group B included two species of Chlorosarcinopsis and two strains of Desmotetra stigmatica (Deason) Deason et Floyd, all of which had parallel thylakoid membranes in pyrenoid matrices, and zoospores bearing apical stigma and subapical flagellar apparatus. The definition of Desmotetra Deason et Floyd was emended to include these features, and Chlorosarcinopsis delicata S. Watanabe was transferred to this genus. Group C comprised Chlorosarcina stigmatica Deason (ASIB.T105), for which we proposed Sarcinochlamys gen. nov., a genus distinct from Chlorosarcina Gerneck in having walled zoospores. Group D, comprising six species, corresponded to Neochlorosarcina and was divided into two subgroups. The presence of thin cell walls in Neochlorosarcina S. Watanabe was ascertained as a valid feature for circumscribing the sarcinoid genera. The physiological experiments on the species of Chlorosarcinopsis and Chlorosarcina by Groover and Bold (1968) were assessed based on the phylogenetic results. Groups (A, B, D) were roughly characterized by these features: algal mass color, utilization of selected nitrogen compounds and carbon sources under light/dark and aerobic/anaerobic conditions, and requirement for vitamin B12. Molecular analysis revealed that Chlorosphaeropsis alveolata Herndon had closer affinity with solitary Protosiphon Klebs and Spongiochloris Starr than with sarcinoid members. © 2005 Phycological Society of America.

DOI： 10.1111/j.1529-8817.2006.00196.x

Scopus

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Nature  

Embryonic stem (ES) cells are pluripotent cells derived from early mammalian embryos1,2. Their immortality and rapid growth make them attractive sources for stem cell therapies3; however, they produce tumours (teratomas) when transplanted, which could preclude their therapeutic usage4. Why ES cells, which lack chromosomal abnormalities, possess tumour-like properties is largely unknown. Here we show that mouse ES cells specifically express a Ras-like gene, which we have named ERas. We show that human HRasp, which is a recognized pseudogene, does not contain reported base substitutions and instead encodes the human orthologue of ERas. This protein contains amino-acid residues identical to those present in active mutants of Ras5 and causes oncogenic transformation in NIH 3T3 cells. ERas interacts with phosphatidylinositol-3-OH kinase6 but not with Raf7,8. ERas-null ES cells maintain pluripotency but show significantly reduced growth and tumorigenicity, which are rescued by expression of ERas complementary DNA or by activated phosphatidylinositol-3-OH kinase. We conclude that the transforming oncogene ERas is important in the tumour-like growth properties of ES cells.

DOI： 10.1038/nature01646

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Molecular and Cellular Biology  

Embryonic stem (ES) cells are immortal and pluripotent cells derived from early mammalian embryos. Transcription factor Oct3/4 is essential for self-renewal of ES cells and early mouse development. However, only a few Oct3/4 target genes have been identified. In this study, we found that F-box-containing protein Fbx15 was expressed predominantly in mouse undifferentiated ES cells. Inactivation of 0ct3/4 in ES cells led to rapid extinction of Fbx15 expression. Reporter gene analyses demonstrated that this ES cell-specific expression required an 18-bp enhancer element located approximately 500 nucleotides upstream from the transcription initiation site. The enhancer contained an octamer-like motif and an adjacent Sox-binding motif. Deletion or point mutation of either motif abolished the enhancer activity. The 18-bp fragment became active in NIH 3T3 cells when Oct3/4 and Sox2 were coexpressed. A gel mobility shift assay demonstrated cooperative binding of Oct3/4 and Sox2 to the enhancer sequence. In mice having a β-galactosidase gene knocked into the Fbx15 locus, 5-bromo-4-chloro-3-indolyl-β-D-galactopyranoside staining was detected in ES cells, early embryos (two-cell to blastocyst stages), and testis tissue. Despite such specific expression of Fbx15, homozygous mutant mice showed no gross developmental defects and were fertile. Fbx15-null ES cells were normal in morphology, proliferation, and differentiation. These data demonstrate that Fbx15 is a novel target of Oct3/4 but is dispensable for ES cell self-renewal, development, and fertility.

DOI： 10.1128/MCB.23.8.2699-2708.2003

担当区分：筆頭著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Biochemical and Biophysical Research Communications  

Cyclin E-Cdk2 is an evolutionary conserved cyclin-dependent kinase (CDK) complex that drives the G1 to S phase transition of the cell cycle. A novel cDNA encoding a HECT family protein also containing RCC1-like repeats was isolated by a yeast two-hybrid screening using both cyclin E and its inhibitor p21. The protein product of this cDNA, Ceb1, interacts with various cyclin subunits of CDKs in mammalian cells. Expression of Ceb1 is specifically detected in testis and ovary and is highly elevated when the functions of the tumor suppressor proteins, p53 and RB, are compromised by mutations or viral oncoproteins. The present results suggest that Ceb1 may play a critical role when its expression and the CDK activity are upregulated by inactivation of p53 and RB.

DOI： 10.1006/bbrc.1999.1777

Scopus

担当区分：筆頭著者   記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Biochemical and Biophysical Research Communications  

p21(Cip1/Waf1) inhibits cell-cycle progression by binding to G1 cyclin/CDK complexes and proliferating cell nuclear antigen (PCNA) through its N- and C-terminal domains, respectively. Here, we report a novel p21(Cip1/Waf1)-interacting protein, Ciz1 (for Cip1 interacting zinc finger protein), which contains polyglutamine repeats and glutamine-rich region in the N-terminus as well as three zinc-finger motifs and one MH3 (matrin 3-homologous domain 3) in the C-terminal region, Ciz1 bound to the N-terminal, the CDK2-interacting part of p21(Cip1/Waf1), and the interaction was disrupted by the overexpression of CDK2. A region of about 150 amino acids containing the first zinc-finger motif in Ciz1 was the binding site for p21(Cip/Waf1). When Ciz1 and p21(Cip/Waf1) were individually overexpressed in U2-OS cells, they mostly localized in the nucleus. However, coexpression of Ciz1 induced cytoplasmic distribution of p21(Cip1/Waf1). These data indicate that Ciz1 is a unique nuclear protein that regulates the cellular localization of p21(Cip/Waf1).

DOI： 10.1006/bbrc.1999.1516

Scopus

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：FEBS Letters  

The N-terminus of MDM2 proto-oncoprotein interacts with p53 and down modulates p53 activity by inhibiting transcriptional activity and promoting p53 degradation. MDMX is structurally related to MDM2 and also binds to p53. However, the function of MDMX has not been clarified yet. We found that MDM2 hetero-oligomerized with MDMX through their C-terminal RING finger domains. Yeast two-hybrid analysis revealed that the hetero-oligomerization between MDMX and MDM2 was more stable than the homo-oligomerization of each protein. MDM2 has been shown to be degraded by the ubiquitin-proteasome pathway, while MDMX was a stable protein. Interaction of MDMX with MDM2 through the C-terminal RING finger domains resulted in inhibiting degradation of MDM2. These data indicate that MDMX functions as a regulator of MDM2. Copyright (C) 1999 Federation of European Biochemical Societies.

DOI： 10.1016/S0014-5793(99)00254-9

Scopus

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Leukemia  

We cloned a novel adaptor protein, APS (adaptor molecule containing Pleckstrin homology (PH) and Src Homology-2 (SH2) domains), which was tyrosine phosphorylated in response to c-kit or B cell receptor stimulation. Here, we report that APS was tyrosine phosphorylated by Janus kinase-2 (JAK2) at its C-terminal tyrosine residue and interacted with c-Cbl. Forced expression of APS in an erythropoietin (EPO)-dependent hematopoietic cell line resulted in reduced activation of STAT5 but not cell proliferation in response to EPO. APS bound to the phosphorylated tyrosine residue, Y343 of the erythropoietin receptor cytoplasmic domain. Co-expression of APS and c-Cbl, but not expression of either alone inhibited EPO-dependent STAT5 activation in 293 cells. This required the C-terminal phosphorylation site, as well as PH and SH2 domains of APS. Therefore, one of the major functions of APS is in recruitment of c-Cbl into the receptor/JAK complex, thereby inhibiting JAK signaling activity.

DOI： 10.1038/sj.leu.2401397

Scopus

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Biochemical and Biophysical Research Communications  

We have reported two JAK-signaling modulators, CIS (cytokine-inducible SH2 protein) and JAB (JAK2 binding protein), which are structurally related. Here we cloned three additional CIS family genes (CIS2, CIS3, and CIS4) on the basis of an expression sequence tag (EST) database search. We also found at least two additional candidates of this gene family in the database. These genes were induced by erythropoietin and granulocyte-macrophage colony stimulating factor in certain hematopoietic cell lines. The SH2 domain and a C-terminal 40 amino acid region, designated the CIS homology domain (CH domain), are highly conserved in this family, while the N-terminal regions of these proteins share little similarity. A yeast two-hybrid assay and in vitro and in vivo binding assays revealed that in addition to JAB, CIS3 bound to the JAK2 tyrosine kinase domain (JH1), although the interaction of CIS3 with the JAK2-JH1 domain was much weaker than that of JAB. Transient expression of JAB and CIS3, but not other CISs, strongly inhibited leukemia inhibitory factor (LIF)-induced STAT3-reporter gene activation in 293 cells. Furthermore, constitutive overexpression of JAB and CIS3 in M1 leukemia cells prevented LIF-induced differentiation and growth arrest. Although the physiological function remains to be investigated, CIS family genes could play a role in the negative regulation of cytokine signaling by interacting with specific targets.

DOI： 10.1006/bbrc.1997.7484

Scopus

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Nature  

The proliferation and differentiation of cells of many lineages are regulated by secreted proteins known as cytokines. Cytokines exert their biological effect through binding to cell-surface receptors that are associated with one or more members of the JAK family of cytoplasmic tyrosine kinases. Cytokine-induced receptor dimerization leads to the activation of JAKs, rapid tyrosine-phosphorylation of the cytoplasmic domains, and subsequent recruitment of various signaling proteins, including members of the STAT family of transcription factors, to the receptor complex. Using the yeast two-hybrid system, we have now isolated a new SH2-domain-containing protein, JAB, which is a JAK-binding protein that interacts with the Jak2 tyrosine-kinase JH1 domain. JAB is structurally related to CIS, a cytokine- inducible SH2 protein. Interaction of JAB with Jak1, Jak2 or Jak3 markedly reduces their tyrosine-kinase activity and suppresses the tyrosine- phosphorylation and activation of STATs. JAB and CIS appear to function as negative regulators in the JAK signalling pathway.

DOI： 10.1038/43213

Scopus

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Blood  

We searched for immediate early cytokine responsive genes and isolated a novel gene, CIS (Cytokine Inducible SH2 containing protein) that is induced in hematopoietic cells by a subset of cytokines including interleukin-2 (IL- 2), IL-3, and erythropoietin (EPO). The mutant IL-2 receptor that fails to activate STAT5 could not induce CIS, suggesting that STATS is involved in the cytokine-inducible expression of CIS. We cloned the 5'-flanking region of the CIS gene and found that about 200 bases upstream of the transcription- initiation site contain four potential STATS binding sites (MGF boxes). Luciferase reporter assays showed that these MGF boxes were essential for EPO-dependent promoter activity. Expression of STAT5 and the EPO receptor in HEK293 cells conferred EPO-dependent activation of the CIS promoter. These data indicate that CIS is a target of the JAK-STAT5 pathway of cytokine receptors. CIS contains an SH2 domain and binds to tyrosine-phosphorylated EPO and IL-3 receptors. In HEK293 cells expressing STAT5 and the EPO receptor, EPO-dependent tyrosine phosphorylation of STAT5, as well as EPO- dependent CIS-promoter activation, was suppressed when CIS was coexpressed. Moreover, the induction of oncostatin M, another STAT5 target, as well as the tyrosine-phosphorylation of STAT5, were partially suppressed by CIS expression in Ba/F3 cells. Thus, CIS is a feedback modulator of STAT5; its expression is induced by STAT5 and it negatively modulates STAT5 activation.

DOI： 10.1182/blood.v89.9.3148

Scopus

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：John Wiley & Sons  

DOI： 10.1111/j.1440-1835.1996.tb00037.x

開催年月日： 2022年3月

記述言語：日本語   会議種別：シンポジウム・ワークショップ パネル（指名）  

開催地：東京・オンライン  

開催年月日： 2021年10月

記述言語：日本語   会議種別：口頭発表（一般）  

開催地：大分・オンライン  

開催年月日： 2021年9月

記述言語：日本語   会議種別：口頭発表（一般）  

開催年月日： 2020年10月

記述言語：日本語   会議種別：口頭発表（一般）  

開催地：鹿児島・オンライン  

開催年月日： 2020年10月

記述言語：日本語   会議種別：シンポジウム・ワークショップ パネル（指名）  

開催地：鹿児島・オンライン  

開催年月日： 2019年11月

記述言語：日本語   会議種別：口頭発表（一般）  

開催地：東京  

開催年月日： 2019年11月

記述言語：日本語   会議種別：口頭発表（一般）  

開催地：福岡  

開催年月日： 2019年3月

記述言語：日本語   会議種別：口頭発表（一般）  

開催地：兵庫  

開催年月日： 2018年12月

記述言語：日本語   会議種別：口頭発表（一般）  

開催地：東京  

開催年月日： 2018年6月

記述言語：英語   会議種別：ポスター発表  

開催地：Melbourne, Australia  

開催年月日： 2017年10月

記述言語：日本語   会議種別：シンポジウム・ワークショップ パネル（指名）  

開催地：種子島、鹿児島県  

開催年月日： 2017年7月

記述言語：日本語   会議種別：シンポジウム・ワークショップ パネル（指名）  

開催地：岡山  

開催年月日： 2017年3月

記述言語：日本語   会議種別：口頭発表（一般）  

開催地：長崎県長崎市  

開催年月日： 2017年3月

記述言語：日本語   会議種別：口頭発表（一般）  

開催地：長崎県長崎市  

開催年月日： 2017年3月

記述言語：日本語   会議種別：口頭発表（一般）  

開催地：長崎県長崎市  

開催年月日： 2017年3月

記述言語：日本語   会議種別：口頭発表（一般）  

開催地：宮城県仙台市  

開催年月日： 2017年3月

記述言語：日本語   会議種別：口頭発表（一般）  

開催地：宮城県仙台市  

開催年月日： 2016年12月

記述言語：日本語   会議種別：口頭発表（一般）  

開催地：東京都  

開催年月日： 2016年11月 - 2016年12月

記述言語：日本語   会議種別：ポスター発表  

開催地：神奈川県横浜市  

開催年月日： 2016年11月 - 2016年12月

記述言語：日本語   会議種別：ポスター発表  

開催地：神奈川県横浜市  

開催年月日： 2016年11月 - 2016年12月

記述言語：英語   会議種別：ポスター発表  

開催地：神奈川県横浜市  

開催年月日： 2016年8月

記述言語：英語   会議種別：ポスター発表  

開催地：Hong Kong  

開催年月日： 2016年7月

記述言語：日本語   会議種別：口頭発表（一般）  

開催地：東京  

開催年月日： 2016年7月

記述言語：日本語   会議種別：口頭発表（一般）  

開催地：東京  

開催年月日： 2016年6月

記述言語：英語   会議種別：ポスター発表  

開催地：San Francisco  

開催年月日： 2016年6月

記述言語：英語   会議種別：ポスター発表  

開催地：San Francisco  

開催年月日： 2016年5月

記述言語：英語   会議種別：ポスター発表  

開催地：Washington, DC  

開催年月日： 2016年3月

記述言語：日本語   会議種別：シンポジウム・ワークショップ パネル（公募）  

開催地：福島県郡山市  

開催年月日： 2016年3月

記述言語：日本語   会議種別：口頭発表（一般）  

開催地：大阪  

開催年月日： 2016年3月

記述言語：日本語   会議種別：口頭発表（一般）  

開催地：大阪  

開催年月日： 2015年10月

記述言語：英語   会議種別：ポスター発表  

開催地：愛知県名古屋市  

開催年月日： 2015年10月

記述言語：英語   会議種別：ポスター発表  

開催地：愛知県名古屋市  

　Incomplete abolition of tumorigenicity creates potential safety concerns in clinical trials of regenerative medicine based on human pluripotent stem cells (hPSCs). Previously, we demonstrated that survivin-responsive conditionally replicating adenoviruses regulated with multiple factors (Surv.m-CRAs), which selectively replicate in and kill a broad range of cancer-cell types, are promising anticancer agents. Here we examined the therapeutic potentials of m-CRAs against hPSCs. The survivin promoter was more active in undifferentiated hPSCs than the TERT promoter, whereas both promoters were minimally active in differentiated normal cells. Accordingly, Surv.m-CRA killed undifferentiated hPSCs more efficiently than Tert.m-CRAs; both m-CRAs exhibited efficient viral replication and cytotoxicity in hPSCs, but not in co-cultured differentiated normal cells. Pre-infection of hPSCs with m-CRA abolished in vivo teratoma formation in a dose-dependent manner following hPSC implantation into mice. Thus, m-CRAs, in particular Surv.m-CRAs, are potentially useful as both potent anticancer drugs and as novel antitumorigenic agents in hPSC-based regenerative medicine.

開催年月日： 2015年7月

記述言語：英語   会議種別：ポスター発表  

開催地：大阪  

開催年月日： 2015年7月

記述言語：日本語   会議種別：口頭発表（一般）  

開催地：大阪  

Human pluripotent stem cells (hPSCs), including human embryonic stem cells (hESCs) and human induced pluripotent stem cells (hiPSCs), are promising sources of material for use in cell transplantation therapy. However, the risk of formation of tumors, including teratomas and cancers originating from contaminating undifferentiated and transformed cells, represents the most critical obstacle to the safe clinical application of hPSC-based regenerative medicine. Multiple approaches have been taken to improve safety by reducing the risk of carcinogenesis. However, most previous studies focused on improving generation of hiPSCs by eliminating potential oncogenic factors, such as the oncogene c-myc, or by integrating the reprogramming transgenes into chromosomes. Although these sorts of strategies, classified here as the first safety approach, reduce the reprogramming-associated oncogenic potential of hiPSCs, they cannot completely eliminate tumorigenic potentials due to the intrinsic characteristics of hPSCs. We previously developed a novel method (adenoviral conditional targeting) that securely isolated target cells from other cell types and undifferentiated hPSCs (Mol Ther. 14(5): 673-683. 2006 ; Cover & News in the issue of the journal). This method, which can increase the efficacy and safety of hPSC-based regenerative medicine by decreasing tumorigenicity, is classified here as the second safety approach. Strategies that can directly target and kill, rather than merely inhibit, tumorigenic cells are classified here as the third safety approach (See Ide’s presentation). Conditionally replicating adenoviruses (CRAs), also called oncolytic adenoviruses, can selectively replicate in and kill cancer cells; consequently, CRAs represent attractive anticancer drugs. Previously, we developed a method for generating CRAs that can target cancers with multiple cancer-specific factors (m-CRAs); this approach further increased cancer specificity without reducing the anticancer effects. We also demonstrated that among candidate m-CRAs, survivin-responsive m-CRA (Surv.m-CRA) is one of the most promising anticancer agents, in two respects: superior cancer specificity (i.e., safety) and therapeutic efficacy relative to clinically tested telomerase reverse transcriptase (TERT)-responsive m-CRAs (Tert.m-CRAs), and strong anticancer effects against currently incurable cancer stem cells. Based on our careful and extensive preclinical studies, we have a plan to start the investigator initiated first-in-human clinical trial of Surv.m-CRA for malignant orthopedic tumors after J-IND approval, hopefully, this year (as presented in a preclinical symposium session). Here, we demonstrate that m-CRAs may also be useful as novel antitumorigenic agents in hPSC-based therapy. We show that the survivin promoter was more active in undifferentiated hPSCs than the TERT promoter, whereas both promoters were minimally active in differentiated normal cells. Accordingly, Surv.m-CRA killed undifferentiated hPSCs more efficiently than Tert.m-CRA; both m-CRAs exhibited efficient viral replication and cytotoxicity in undifferentiated hPSCs, but not in co-cultured differentiated normal cells. Pre-infection of hPSCs with Surv.m-CRA or Tert.m-CRA abolished in vivo teratoma formation in a dose- dependent manner following hPSC implantation into mice. Thus, we demonstrate that m-CRAs, in particular Surv.m-CRAs, are potentially useful as both potent anticancer drugs and as novel antitumorigenic agents in hPSC-based regenerative medicine; in the latter context, the viruses act by specifically killing contaminating undifferentiated hPSCs.

開催年月日： 2015年3月

記述言語：日本語  

開催地：神奈川  

国内学会

開催年月日： 2015年3月

記述言語：日本語  

開催地：神奈川  

国内学会

開催年月日： 2015年1月

記述言語：日本語  

開催地：鹿児島  

研究会

開催年月日： 2014年3月

記述言語：日本語  

開催地：京都  

国内学会

開催年月日： 2014年1月

記述言語：日本語  

開催地：鹿児島  

研究会

開催年月日： 2014年1月

記述言語：日本語  

開催地：鹿児島  

研究会

開催年月日： 2013年1月

記述言語：日本語  

開催地：鹿児島  

研究会

開催年月日： 2012年6月

記述言語：日本語  

開催地：熊本  

国内学会

開催年月日： 2012年6月

記述言語：日本語  

開催地：神奈川  

国内学会

開催年月日： 2012年6月

記述言語：日本語  

開催地：神奈川  

国内学会

開催年月日： 2012年6月

記述言語：日本語  

開催地：神奈川  

国内学会

開催年月日： 2012年1月

記述言語：日本語  

開催地：鹿児島  

研究会

開催年月日： 2010年12月

記述言語：日本語  

開催地：長崎  

国内学会

開催年月日： 2010年7月

記述言語：日本語  

開催地：栃木  

国内学会

開催年月日： 2010年3月

記述言語：日本語  

開催地：広島  

国内学会

開催年月日： 2010年3月

記述言語：英語  

開催地：福岡  

国際学会

記述言語：日本語   会議種別：ポスター発表  

対象： 高校生

種別：出前授業

「幹細胞と再生医学」についての講義