KATAOKA Hiroaki

写真a

Affiliation

Director

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Degree 【 display / non-display

  • Doctor (Medical Science) ( 1988.9   Miyazaki Medical College )

  • 医学士 ( 1982.3   宮崎医科大学 )

Research Areas 【 display / non-display

  • Life Science / Experimental pathology

  • Life Science / Human pathology

  • Life Science / Molecular biology

 

Papers 【 display / non-display

  • Insufficiency of hepatocyte growth factor activator inhibitor‐1 confers lymphatic invasion of tongue carcinoma cells. Reviewed International journal

    Izumi A, Yamamoto K, Kawaguchi M, Yamashita F, Fukushima T, Kiwaki T, Tanaka H, Yamashita Y, Kataoka H

    Cancer Science   113 ( 6 )   2179 - 2193   2022.4

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

    Hepatocyte growth factor (HGF) activator inhibitor type-1 (HAI-1), encoded by the SPINT1 gene, is a transmembrane protease inhibitor that regulates membrane-anchored serine proteases, particularly matriptase. Here, we explored the role of HAI-1 in tongue squamous cell carcinoma (TSCC) cells. An immunohistochemical study of HAI-1 in surgically resected TSCC revealed the cell surface immunoreactivity of HAI-1 in the main portion of the tumor. The immunoreactivity decreased in the infiltrative front, and this decrease correlated with enhanced lymphatic invasion as judged by podoplanin immunostaining. In vitro homozygous deletion of SPINT1 (HAI-1KO) in TSCC cell lines (HSC3 and SAS) suppressed the cell growth rate but significantly enhanced invasion in vitro. The loss of HAI-1 resulted in enhanced pericellular activities of proteases, such as matriptase and urokinase-type plasminogen activator, which induced activation of HGF/MET signaling in the co-culture with pro-HGF-expressing fibroblasts and plasminogen-dependent plasmin generation, respectively. The enhanced plasminogen-dependent plasmin generation was abrogated partly by matriptase silencing. Culture supernatants of HAI-1KO cells had enhanced potency for converting the proform of vascular endothelial growth factor-C (VEGF-C), a lymphangiogenesis factor, into the mature form in a plasminogen-dependent manner. Furthermore, HGF significantly stimulated VEGF-C expression in TSCC cells. Orthotopic xenotransplantation into nude mouse tongue revealed enhanced lymphatic invasion of HAI-1KO TSCC cells compared to control cells. Our results suggest that HAI-1 insufficiency leads to dysregulated pericellular protease activity, which eventually orchestrates robust activation of protease-dependent growth factors, such as HGF and VEGF-C, in a tumor microenvironment to contribute to TSCC progression.

    DOI: 10.1111/cas.15346

  • Role of the polycystic kidney disease domain in matriptase chaperone activity and localization of hepatocyte growth factor activator inhibitor-1. Reviewed International coauthorship International journal

    Yamashita F, Kaieda T, Shimomura T, Kawaguchi M, Lin C-Y, Johnson MD, Tanaka H, Kiwaki T, FukushimaT, Kataoka H.

    FEBS Journal   2022.1

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

    Hepatocyte growth factor activator inhibitor-1 (HAI-1, also known as SPINT1) is an inhibitor of matriptase, a type-2 transmembrane protease widely expressed in epithelial cells. HAI-1 also functions as a chaperone to maintain the processing and localization of matriptase required for epithelial integrity. However, mechanisms underpinning the chaperone function remain to be elucidated. Here, we show that the first Kunitz domain (KD1) and the adjacent polycystic kidney disease (PKD) domain-like internal domain of HAI-1 are essential for the chaperone function. In HEK293T cells, which do not express endogenous HAI-1 or matriptase, forced matriptase overexpression was unsuccessful unless sufficient HAI-1 was co-expressed. Among mutant HAI-1 constructs, HAI-1 with inactivation mutation in KD1 (HAI-1mKD1) or HAI-1 lacking the PKD domain (HAI-1dPKD) was unable to support matriptase expression, and neither mutant formed a complex with activated matriptase. Matriptase did not localize to the cell surface when co-expressed with HAI-1dPKD. Moreover, HAI-1dPKD accumulated in the cytoplasm of HEK293T and HaCaT cells rather than localizing to the cell surface, presumably due to misfolding as judged by altered antibody recognition. On the other hand, activation-locked and activity-incompetent matriptase were stable and readily overexpressed and localized to the cell surface without HAI-1. Therefore, the observed matriptase instability was caused by its own catalytic activity in the absence of inhibitory HAI-1. The matriptase chaperone function of HAI-1 is thus mediated primarily by the inhibition of undesired intracellular matriptase activity, and the PKD domain is essential for the proper folding and trafficking of inhibitory HAI-1 and its chaperone function.

    DOI: 10.1111/febs.16348

  • The physiological TMPRSS2 inhibitor HAI-2 alleviates SARS-CoV-2 infection. Journal of Virology Reviewed

    Tomita Y, Matsuyama S, Fukuhara H, Maenaka K, Kataoka H, Hashiguchi T, Takeda M

    Journal of Virology   95 ( 12 )   e00434-21   2021.3

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

    DOI: 10.1128/JVI.00434-21

  • Proteolytic cleavage of podocin by matriptase exacerbates podocyte injury. Reviewed International journal

    Ozawa S, Matsubayashi M, Nanaura H, Yanagita M, Mori K, Asanuma K, Kajiwara N, Hayashi H, Ohashi H, Kasahara M, Yokoi H, Kataoka H, Mori E, Nakagawa T

    Journal of Biological Chemistry   295 ( 47 )   16002 - 16012   2020.11

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

    Podocyte injury is a critical step toward the progression of renal disease and is often associated with a loss of slit diaphragm proteins, including Podocin. Although there is a possibility that the extracellular domain of these slit diaphragm proteins can be a target for a pathological proteolysis, the precise mechanism driving the phenomenon remains unknown. Here we show that Matriptase, a membrane-anchored protein, was activated at podocytes in CKD patients and mice, whereas Matriptase inhibitors slowed the progression of mouse kidney disease. The mechanism could be accounted for by an imbalance favoring Matriptase over its cognate inhibitor, hepatocyte growth factor activator inhibitor type 1 (HAI-1), because conditional depletion of HAI-1 in podocytes accelerated podocyte injury in mouse model. Matriptase was capable of cleaving Podocin, but such a reaction was blocked by either HAI-1 or dominant-negative Matriptase. Furthermore, the N terminus of Podocin, as a consequence of Matriptase cleavage of Podocin, translocated to nucleoli, suggesting that the N terminus of Podocin might be involved in the process of podocyte injury. Given these observations, we propose that the proteolytic cleavage of Podocin by Matriptase could potentially cause podocyte injury and that targeting Matriptase could be a novel therapeutic strategy for CKD patients.

    DOI: 10.1074/JBC.RA120.013721

    Other Link: https://doi.org/10.1074/JBC.RA120.013721

  • Protease-activated receptor-2 accelerates intestinal tumor formation through activation of nuclear factor-κB signaling and tumor angiogenesis in ApcMin/+ mice. Reviewed International coauthorship International journal

    Kawaguchi M, Yamamoto K, Kataoka H, Izumi A, Yamashita F, Kiwaki T, Nishida T, Camerer E, Fukushima T

    Cancer science   111 ( 4 )   1193 - 1202   2020.2

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

    Hepatocyte growth factor activator inhibitor-1 (HAI-1), encoded by the SPINT1 gene, is a membrane-bound protease inhibitor expressed on the surface of epithelial cells. Hepatocyte growth factor activator inhibitor-1 regulates type II transmembrane serine proteases that activate protease-activated receptor-2 (PAR-2). We previously reported that deletion of Spint1 in ApcMin/+ mice resulted in accelerated formation of intestinal tumors, possibly through enhanced nuclear factor-κB signaling. In this study, we examined the role of PAR-2 in accelerating tumor formation in the ApcMin/+ model in the presence or absence of Spint1. We observed that knockout of the F2rl1 gene, encoding PAR-2, not only eliminated the enhanced formation of intestinal tumors caused by Spint1 deletion, but also reduced tumor formation in the presence of Spint1. Exacerbation of anemia and weight loss associated with HAI-1 deficiency was also normalized by compound deficiency of PAR-2. Mechanistically, signaling triggered by deregulated protease activities increased nuclear translocation of RelA/p65, vascular endothelial growth factor expression, and vascular density in ApcMin/+ -induced intestinal tumors. These results suggest that serine proteases promote intestinal carcinogenesis through activation of PAR-2, and that HAI-1 plays a critical tumor suppressor role as an inhibitor of matriptase, kallikreins, and other PAR-2 activating proteases.

    DOI: 10.1111/cas.14335

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Books 【 display / non-display

  • Extracellular targeting of cell signaling in cancer.

    Kataoka H, Shimomura T( Role: Contributor ,  HGF Activator (HGFA) and its inhibitors HAI-1 and HAI-2: Key players in tissue repair and cancer )

    Wiley  2018.7 

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    Total pages:462   Responsible for pages:69-90   Language:English Book type:Scholarly book

  • Regulation of Signal Transduction in Human Cell Research

    Kataoka H, Fukushima T( Role: Contributor)

    Springer Nature  2018.3 

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    Total pages:218   Responsible for pages:183-197   Language:English Book type:Scholarly book

  • Glutathione

    Ishida Y, Yukizaki C, Okayama A, Kataoka H( Role: Joint author)

    Nova Science Publishers  2015.3 

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    Total pages:215   Responsible for pages:127-144   Language:English Book type:Scholarly book

  • Handbook of Proteolytic Enzymes (Third Edition)

    Kataoka H( Role: Joint author ,  Chapter 660: Hepatocyte Growth Factor Activator)

    Academic Press (Elsevier)  2013.1 

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    Language:English Book type:Scholarly book

  • Molecular Targets of CNS Tumors

    Fukushima T, Kataoka H( Role: Joint author)

    InTech  2011.9 

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    Language:English Book type:Scholarly book

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MISC 【 display / non-display

  • Hepatocyte growth factor activator inhibitors (HAI-1 and HAI-2): emerging key players in epithelial integrity and cancer. Invited Reviewed International journal

    Kataoka H, Kawaguchi M, Fukushima T, Shimomura T

    Pathology International   68 ( 3 )   145 - 158   2018.3

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    Authorship:Lead author, Corresponding author   Language:English   Publishing type:Article, review, commentary, editorial, etc. (scientific journal)  

    The growth, survival, and metabolic activities of multicellular organisms at the cellular level are regulated by intracellular signaling, systemic homeostasis and the pericellular microenvironment. Pericellular proteolysis has a crucial role in processing bioactive molecules in the microenvironment and thereby has profound effects
    on cellular functions. Hepatocyte growth factor activator inhibitor type 1 (HAI-1) and HAI-2 are type I transmembrane serine protease inhibitors expressed by most epithelial cells. They regulate the pericellular activities of circulating hepatocyte growth factor activator and cellular type II transmembrane serine proteases (TTSPs), proteases required for the activation of hepatocyte growth factor (HGF)/scatter factor (SF). Activated HGF/SF transduces pleiotropic signals through its receptor tyrosine kinase, MET (coded by the protooncogene
    MET), which are necessary for cellular migration,
    survival, growth and triggering stem cells for
    accelerated healing. HAI-1 and HAI-2 are also required for normal epithelial functions through regulation of TTSP-mediated activation of other proteases and protease-activated receptor 2, and also through suppressing excess degradation of epithelial junctional proteins. This review summarizes current knowledge regarding the mechanism of pericellular HGF/SF activation and highlights emerging roles of HAIs in epithelial development
    and integrity, as well as tumorigenesis and progression of transformed epithelial cells.

    DOI: 10.1111/pin.12647

  • 新たな上皮完全性維持機構 - 細胞膜結合型セリンプロテアーゼとインヒビター. Invited

    片岡 寛章

    実験医学   36 ( 3 )   438 - 444   2018.2

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    Authorship:Lead author, Corresponding author   Language:Japanese   Publishing type:Article, review, commentary, editorial, etc. (scientific journal)   Publisher:羊土社  

  • Mechanisms of hepatocyte growth factor activation in cancer tissues. International journal

    Kawaguchi M, Kataoka H.

    Cancers   6 ( 4 )   1890 - 1904   2014.9

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    Authorship:Corresponding author   Language:English   Publishing type:Article, review, commentary, editorial, etc. (scientific journal)   Publisher:MDPI AG  

    Hepatocyte growth factor/scatter factor (HGF/SF) plays critical roles in cancer progression through its specific receptor, MET. HGF/SF is usually synthesized and secreted as an inactive proform (pro-HGF/SF) by stromal cells, such as fibroblasts. Several serine proteases are reported to convert pro-HGF/SF to mature HGF/SF and among these, HGF activator (HGFA) and matriptase are the most potent activators. Increased activities of both proteases have been observed in various cancers. HGFA is synthesized mainly by the liver and secreted as an inactive pro-form. In cancer tissues, pro-HGFA is likely activated by thrombin and/or human kallikrein 1-related peptidase (KLK)-4 and KLK-5. Matriptase is a type II transmembrane serine protease that is expressed by most epithelial cells and is also synthesized as an inactive zymogen. Matriptase activation is likely to be mediated by autoactivation or by other trypsin-like proteases. Recent studies revealed that matriptase autoactivation is promoted by an acidic environment. Given the mildly acidic extracellular environment of solid tumors, matriptase activation may, thus, be accelerated in the tumor microenvironment. HGFA and matriptase activities are regulated by HGFA inhibitor (HAI)-1 (HAI-1) and/or HAI-2 in the pericellular microenvironment. HAIs may have an important role in cancer cell biology by regulating HGF/SF-activating proteases.

    DOI: 10.3390/cancers6041890

  • Hepatocyte growth factor activator (HGFA): pathophysiological functions in vivo. Invited Reviewed International journal

    Kataoka H, Kawaguchi M

    FEBS Joural   277 ( 10 )   2230 - 2237   2010.5

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    Language:English   Publishing type:Article, review, commentary, editorial, etc. (scientific journal)   Publisher:Federation of European Biochemical Societies  

    Hepatocyte growth factor activator (HGFA) is a serine protease initially identified as a potent activator of hepatocyte growth factor/scatter factor. Hepatocyte growth factor/scatter factor is known to be critically involved in tissue morphogenesis, regeneration, and tumor progression, via its receptor, MET. In vivo, HGFA also activates macrophage-stimulating protein, which has roles in macrophage recruitment and inflammatory processes, cellular survival and wound healing through its receptor, RON. Therefore, the pericellular activity of HGFA might be an important factor regulating the activities of these multifunctional cytokines in vivo. HGFA is secreted mainly by the liver, circulates in the plasma as a zymogen (pro-HGFA), and is activated in response to tissue injury, including tumor growth. In addition, local production of pro-HGFA by epithelial, stromal or tumor cells has been reported. Although the generation of HGFA-knockout mice revealed that the role played by HGFA in normal development and physiological settings can be compensated for by other protease systems, HGFA has important roles in regeneration and initial macrophage recruitment in injured tissue in vivo. Insufficient activity of HGFA results in impaired regeneration of severely damaged mucosal epithelium, and may contribute to the progression of fibrotic lung diseases. On the other hand, deregulated excess activity of HGFA may be involved in the progression of some types of cancer.

    DOI: 10.1111/j.1742-4658.2010.07640.x

    Other Link: https://febs.onlinelibrary.wiley.com/doi/10.1111/j.1742-4658.2010.07640.x

  • Roles of hepatocyte growth factor (HGF) activator and HGF activator inhibitor in the pericellular activation of HGF/scatter factor. Reviewed International journal

    Kataoka H, Miyata S, Uchinokura S, Itoh H.

    Cancer and Metastasis Reviews   22   223 - 236   2003.9

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    Authorship:Lead author, Corresponding author   Language:English   Publishing type:Article, review, commentary, editorial, etc. (scientific journal)   Publisher:Kluwer Academic Publishers  

    The activation of hepatocyte growth factor (HGF)/scatter factor (SF) in an extracellular milieu is a critical limiting step in HGF/SF-induced signaling that is believed to have important roles in invasive growth of tumor cells and regeneration of injured tissue. This activation is caused by a proteolytic cleavage at the bond between Arg494-Val495 in the single-chain HGF/SF precursor, generating an active two-chain heterodimeric form. The HGF activator (HGFA) is a coagulation factor XII-like serine proteinase critically involved in this process in injured tissues including tumor tissues. In the past several years, the identification of endogenous HGFA inhibitors (HAIs) has provided detailed knowledge of the regulation of HGFA activity. Currently, two types of HAIs, namely HAI-1 and HAI-2, have been reported. Both are Kunitz-type serine proteinase inhibitors and inhibit not only HGFA but also other serine proteinases, such as membrane-type serine protease 1 (matriptase), plasmin, trypsin and kallikreins. HAIs are of particular interest because they are synthesized as type-I transmembrane proteins. Therefore, HAIs must have important regulatory roles in a cell surface proteolytic reaction, which has emerged as an important mechanism for the generation of biologically active proteins mediating a diverse range of cellular functions. This review is a summary and interpretation of recent data regarding the regulation of pericellular HGF/SF activation mediated by HGFA and HAIs and includes a discussion of the possible role of the type I transmembrane Kunitz-type inhibitor in pericellular proteolysis.

    DOI: 10.1023/a:1023051500010 Abstract

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Presentations 【 display / non-display

  • HAI-2/SPINT2 maintains epithelial architecture in digestive tracts Invited International conference

    Kataoka H, Yamamoto K, Kawaguchi M

    ASBMB Special Symposia Series; Serine Proteases in Pericellular Proteolysis and Signaling 

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    Event date: 2019.9.12 - 2019.9.15

    Language:Japanese   Presentation type:Oral presentation (invited, special)  

  • プロテアーゼと腫瘍間質 Invited

    片岡 寛章

    第107回 日本病理学会総会 

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    Event date: 2018.6.21 - 2018.6.23

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

  • Hai-2 is essential for the maintenance of intestinal epithelium in mice. International conference

    Kataoka H, Kawaguchi M, Yamamoto K, Seto A, Fukushima T, Shimomura T, Takeda N

    ASBMB Special Symposia Series; Membrane-Anchored Serine Proteases  (Potomac, MD, USA)  American Society for Biochemistry and Molecular Biology

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    Event date: 2017.9.14 - 2017.9.17

    Language:English   Presentation type:Oral presentation (general)  

    Venue:Potomac, MD, USA  

  • Accelerated tumor formation induced by Hai-1 deficiency in the ApcMin/+ model is prevented by concomitant deficiency of Par-2. International conference

    Kawaguchi M, Yamamoto K, Fukushima T, Camerer E, Kataoka H

    ASBMB Special Symposia Series; Membrane-Anchored Serine Proteases  (Potomac, MD, USA)  American Society for Biochemistry and Molecular Biology

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    Event date: 2017.9.14 - 2017.9.17

    Language:English   Presentation type:Oral presentation (general)  

    Venue:Potomac, MD, USA  

  • 細胞周囲微小環境におけるプロテアーゼ活性制御とその破綻がもたらす上皮組織の病態(病理学会宿題報告). Invited

    片岡 寛章

    第106回日本病理学会総会  (東京都)  日本病理学会

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    Event date: 2017.4.27 - 2017.4.30

    Language:Japanese   Presentation type:Oral presentation (invited, special)  

    Venue:東京都  

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Awards 【 display / non-display

  • 日本病理学賞

    2017.4   日本病理学会   細胞周囲微小環境におけるプロテアーゼ活性制御とその破綻がもたらす上皮組織の病態

    片岡寛章

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    Award type:Award from Japanese society, conference, symposium, etc.  Country:Japan

  • 日本病理学会学術研究賞(A演説)

    2000.11   日本病理学会  

    片岡寛章

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    Award type:Award from Japanese society, conference, symposium, etc.  Country:Japan

  • 日本ヒト細胞学会学術賞

    2000.8   日本ヒト細胞学会  

    片岡寛章

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    Award type:Award from Japanese society, conference, symposium, etc.  Country:Japan

Grant-in-Aid for Scientific Research 【 display / non-display

  • 細胞膜結合型セリンプロテアーゼインヒビターによる上皮完全性維持と癌抑制機構

    2016.04 - 2020.03

    科学研究費補助金  基盤研究(B)

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    Authorship:Principal investigator 

  • 上皮組織における細胞膜上プロテアーゼ制御機構の破綻が引き起こす病態の解析

    2012.04 - 2016.03

    科学研究費補助金  基盤研究(B)

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    上皮組織における細胞膜上プロテアーゼ制御機構の破綻が引き起こす病態の解析

  • 上皮細胞膜上におけるプロテアーゼ活性調節とその異常による病態の解析

    2008.04 - 2012.03

    科学研究費補助金  基盤研究(B)

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    Authorship:Principal investigator 

    上皮細胞膜上におけるプロテアーゼ活性調節とその異常による病態の解析

  • 胃腸管粘膜上皮組織の修復と再生における分子機構

    2005.04 - 2008.03

    科学研究費補助金  基盤研究(B)

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    Authorship:Principal investigator 

    胃腸管の粘膜再生修復のプロセスには様々な因子が複雑に関わっているが、なかでも増殖因子産生とその活性化、細胞周囲微小環境におけるプロテアーゼ活性調節、そして上皮細胞の分化誘導因子が重要な役割を果たすと考えられる。我々はこれまでに、強力な胃腸管粘膜再生因子である肝細胞増殖因子(HGF)の活性化機構について精力的に研究を行い、その分子機構を明らかにしてきた。その結果、HGF活性化酵素の一つである HGF activator 遺伝子を破壊したマウスでは、傷害腸管粘膜上皮の初期再生が顕著に遅延することを明らかにした。更に細胞周囲におけるHGF activator の至適活性は、粘膜上皮細胞の細胞膜上に存在する膜結合クニッツ型インヒビター “HGF activator inhibitor type 1 (HAI-1)”により調節されることも明らかにした。そこで、HAI-1遺伝子破壊マウスを作成したところ、ホモマウスは胎生致死であり、HAI-1が代償の効かない重要な生体内機能を有することが明らかとなった。類似の膜型インヒビターであるHAI-2とamyloid β protein precursor (APP)も粘膜上皮に発現し増殖に関与することも示した。更に、胃腸管上皮の分化に伴い核に移行するが、傷害粘膜修復初期には細胞質にとどまる新規ペプチドH2RSP (HAI-2-related small peptide) を見出した。
    上記のこれまでの研究成果をもとに、本研究では傷害粘膜上皮の修復・再生におけるこれらHGF活性化関連蛋白と膜結合型インヒビター、そしてH2RSPの機能を主にin vivoで解明し、傷害粘膜の修復・再生、特に初期修復における分子機構を解明することを目的としている。具体的には;(1) HGF activator ノックアウトマウスを用いた傷害粘膜初期修復遅延モデルを用い、再生上皮の遺伝子発現の網羅的解析を対照マウスと比較して行い、上皮の初期再生に重要なシグナルの流れを解析する。(2) HAI-1 ノックアウトマウスの表現形を解析すると共に、培養上皮細胞を用いてHAI-1 発現のノックダウンと、HAI-1 に結合している細胞内蛋白の同定を行い、HAI-1の機能を解明する。(3) 培養細胞を用いてH2RSP発現のノックダウンを行い、H2RSPの機能の一端を明らかにする。(4) これらの蛋白の消化管粘膜疾患における臨床病理学的意義を検討し、また、これらを利用した粘膜再生治療のための基礎実験を行う。

  • 胃腸管粘膜の再生修復における分子機構の解明

    2002.04 - 2005.03

    科学研究費補助金  基盤研究(B)

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    Authorship:Principal investigator 

     細胞膜表面においては、種々の増殖因子前駆体や細胞外基質分解酵素前駆体の活性化とその制御が活発に行なわれ、細胞の増殖や分化、遊走・浸潤に重要な意義を持っている。研究代表者はプロテアーゼと細胞膜結合型プロテアーゼインヒビターによるこれらの活性化反応とその制御機構、そしてこれらの反応がさまざまな病態において持つ意義について研究を行なってきた。
     本研究では、これらのプロテアーゼと膜型インヒビターによる生理活性物質活性化調節機構の胃腸管粘膜上皮の再生修復における意義を、多機能増殖因子として胃腸管粘膜再生においても重要な役割を有することが分っている肝細胞増殖因子 (HGF) の活性化機構に焦点をあて、研究を行なった。その結果、胃腸管粘膜上皮初期再生における HGF 活性化機構の重要性を証明することが出来た。また、HGF活性化酵素 (HGF activator) のインヒビターである、細胞膜結合型プロテアーゼインヒビター“HAI-1”が、予想外の、しかし極めて重要な生体内機能を有していることも明らかとなった。本研究の過程で作成した HGF activator のノックアウトマウスと、HAI-1 のノックアウトマウスは、今後、当該分野における必要不可欠なツールとなると思われる。
     本研究では、更に、胃腸管上皮細胞に発現している新規の核移行蛋白である H2RSP についても検討を行なった。その結果、H2RSP が上皮細胞の増殖停止と分化に伴って核に移行することを見出した。
     なお、本研究の遂行にあたっては研究分担者の伊藤浩史助教授をはじめ、宮崎大学医学部病理学第二講座の教室員と大学院生の諸君(秋山裕、瀬口智子、長沼誠二、宮田史朗、内之倉俊朗、内山周一郎、田中弘之、長池幸樹、福島剛、長井美由紀、小濱和代)の多大な協力があった。

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  • Editor-in-Chief, Human Cell (Springer Nature)

    2013.04

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    Editor-in-Chief, Human Cell (Electronic ISSN: 1749-0774, Springer Nature)