KEIO RESEARCHERS INFORMATION SYSTEM

Career 【 Display / hide 】

Career 【 Display / hide 】

• 2025.04

  -

  Present

  Keio University Hospital, Department of Dentistry and Oral Surgery, Chief Physician

• 2023.04

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  Present

  Keio University Hospital, Center for Perinatal and Pediatric Care

• 2024.10

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  Present

  Keio University School of Medicine, Department of Dentistry and Oral Surgery, Senior Assistant Professor / Lecturer (full time)

• 2021.04

  -

  2024.09

  Keio University School of Medicine, Department of Dentistry and Oral Surgery, Assistant Professor

• 2018.04

  -

  2020.03

  Keio University, Graduate School of Medicine, Assistant Professor

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Academic Background 【 Display / hide 】

Academic Background 【 Display / hide 】

• 2017.04

  -

  2021.03

  Keio University, Graduate School of Medicine, Keio University

  Graduate School, Completed, Doctoral course

• 2017.04

  -

  2021.03

  The Keio University Graduate School of Medicine, 医学研究科博士課程, 医学研究系専攻

Academic Degrees 【 Display / hide 】

Academic Degrees 【 Display / hide 】

• Ph.D.in Medicine, Keio University, Coursework, 2021.03

  Tooth extraction in mice administered zoledronate increases inflammatory cytokine levels and promotes osteonecrosis of the jaw

Licenses and Qualifications 【 Display / hide 】

Licenses and Qualifications 【 Display / hide 】

• （公社）日本口腔外科学会認定口腔外科指導医, 2024.04

• （公社）日本化学療法学会認定抗菌化学療法認定歯科医師, 2016.01

• （公社）日本口腔外科学会認定口腔外科専門医, 2020.04

• （一社）日本歯科専門医機構認定口腔外科専門医, 2020.04

• 日本がん治療認定医機構がん治療認定医 （歯科口腔外科）, 2021.04

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Research Areas 【 Display / hide 】

Research Areas 【 Display / hide 】

• Life Science / Surgical dentistry

• Life Science / Tumor biology

Research Keywords 【 Display / hide 】

Research Keywords 【 Display / hide 】

• Medication-Related OsteoNecrosis of the Jaw (MRONJ)

• Bone metabolism

• Osteoclast

• Patient-dervied xenografts

• Oral cancer

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Books 【 Display / hide 】

Books 【 Display / hide 】

• デンタルダイヤモンド 2022年2月号【巻頭特集】GPの疑問に答える！ 歯科小手術の勘どころ

  相馬智也, デンタルダイヤモンド社, 2022.02

  Scope: 粘液嚢胞・エプーリスの除去を安全に行うには？

• よくわかる歯科小手術の基本―抜歯から歯周外科まで

  相馬智也, 莇生田整治, デンタルダイヤモンド社, 2016.10,  Page： 141

  Scope: 全身状態・疾患への配慮

Papers 【 Display / hide 】

Papers 【 Display / hide 】

• Mucoepidermoid carcinoma of the hard palate in a 7-year-old boy: A case report

  相馬智也, 内山公男, 安井佑太, 山田学, 岩渕博史, 莇生田整治

  小児口腔外科 36 ( 1 ) 11 - 16 2026.06

  Lead author, Accepted

• Antibacterial silver ion-coated dental implants suppress peri-implantitis in a murine model

  Mana Nasu, Tomoya Soma, Hidetaka Miyashita, Takehito Ouchi, Yoshitaka Kase, Takazumi Yasui, Fuka Homma, Kitaru Suzuki, Takeshi Miyamoto, Hideyuki Okano, Masaya Nakamura, Taneaki Nakagawa, Mamoru Aizawa, Satoru Morikawa

  Scientific Reports (Springer Science and Business Media LLC)  16 ( 1 )  2026.05

  Lead author, Accepted,  ISSN  2045-2322

  　View Summary

  Abstract
  
  Peri-implantitis, an inflammatory condition caused by bacterial infection around an implant, is currently the leading cause of implant failure. Porphyromonas gingivalis ( P. gingivalis ), an anaerobic bacterial pathogen associated with periodontitis, is known to play a key role in peri-implantitis. To address this issue, the present study examined the antibacterial properties of silver ion (Ag ⁺ )-coated titanium implants against P. gingivalis and their ability to prevent bone loss. Ag ⁺ -coated implants, i.e., Ti implants coated with Ag ⁺ ions on a hydroxyapatite film chelated with inositol hexaphosphate, demonstrated significant antibacterial activity against P. gingivalis in the Ti wire configuration in inhibition zone assays ( n  = 4 per group). Furthermore, in a murine model of ligature-induced peri-implantitis, these implants significantly reduced alveolar bone resorption compared to uncoated titanium controls. This preclinical study suggests that applying an Ag ⁺ coating to dental implants is an effective strategy for preventing P. gingivalis –induced peri-implantitis. In the control group, bone loss of 19–25% relative to baseline was observed at day 28, whereas the Ag ⁺ -coated group exhibited only 15–20% bone loss ( n  = 8 per group per time point). These findings suggest the potential of Ag ⁺ coating as a preventive strategy against peri-implantitis-associated bone loss.

  • Access to Document (DOI)

• Drug Repurposing Screen Identifies Pimozide as a ROS-Inducing Therapy with Anti-tumor Efficacy in HNSCC PDX Models

  Shogo Okazaki, Shintaro Nakamura, Tomoya Soma, Momoko Yoshikawa, Seiji Asoda, Yurika Nakajima, Kenji Tsuchihashi, Mitsuyo Ohmura, Ryo Goitsuka, Kenichi Imai, Hideyuki Saya, Osamu Nagano, Hiroyuki Ozawa

  Cancer Science (Wiley)  117 ( 2 ) 511 - 521 2026.02

  Accepted,  ISSN  1347-9032

  　View Summary

  ABSTRACT
  
  Redox regulation is a key mechanism supporting tumor survival and an attractive therapeutic target. In this study, we screened 1161 FDA‐approved compounds to identify agents that induce reactive oxygen species (ROS) accumulation in head and neck squamous cell carcinoma (HNSCC) cells. Pimozide, a dopamine D2 receptor antagonist, emerged as the most potent ROS inducer. It selectively suppresses the growth of HNSCC cells with high oxidative stress resistance while exhibiting only modest effects on less resistant cells and normal keratinocytes. Notably, pimozide exhibited anti‐tumor effects as a monotherapy and in combination with paclitaxel at clinically relevant doses. Mechanistic analysis revealed that pimozide rapidly induced ROS accumulation via a mechanism distinct from its known action on dopamine D2 receptors and STAT3/5. To identify markers of ROS‐induced responses, we examined ROS‐responsive genes and found that early growth response 1 (EGR1) was selectively induced in sensitive cells and correlated with pimozide responsiveness. Functional analysis revealed that EGR1 knockdown suppressed pimozide‐induced cytotoxicity, suggesting its role as a functional pharmacodynamic marker of pimozide sensitivity. In a patient‐derived xenograft model of HNSCC, pimozide significantly reduced the tumor burden alone and in combination with paclitaxel. While tumor volume reduction in the combination group was not statistically greater than that in the monotherapy group, fluorescence immunohistochemistry revealed a marked decrease in undifferentiated tumor cells, indicating enhanced therapeutic effects of combination treatment. Taken together, these findings indicate that pimozide is a promising candidate for repurposing as a novel therapeutic agent against HNSCC.

  • Access to Document (DOI)

• DC-STAMP and OC-STAMP cooperatively regulate osteoclast and foreign body giant cell cell-cell fusion

  Fuka Homma, Ryotaro Iwasaki, Makoto Tateyama, Tomoya Soma, Mayu Morita, Makiko Kashio, Taneaki Nakagawa, Takeshi Miyamoto

  Journal of Bone and Mineral Metabolism (Springer Science and Business Media LLC)  44 ( 1 ) 39 - 48 2026.01

  Accepted,  ISSN  0914-8779

  　View Summary

  Abstract
  
  Introduction
  
  Osteoclasts and foreign body giant cells (FBGCs) are multi-nuclear cells established by fusion of their mono-nuclear forms. Multi-nucleation via cell–cell fusion is a common characteristic of osteoclasts and FBGCs, and Dendritic Cell-Specific Transmembrane Protein (DC-STAMP) and Osteoclast Stimulatory Transmembrane Protein (OC-STAMP) are both required for the process. Thus, it is thought that DC-STAMP and OC-STAMP interaction likely induces this fusion, but details of these mechanisms are not clear.
  
  Materials and methods
  
  We crossed DC-STAMP knockout (KO) with OC-STAMP KO mice to obtain DC-STAMP/OC-STAMP doubly deficient (DKO) mice. Osteoclasts and FBGC common progenitors were isolated from wild-type (WT), DC-STAMP KO, OC-STAMP KO or DKO mice. We then set up 4 co-culture systems: (1) WT with DC-STAMP KO cells, (2) WT with OC-STAMP KO cells, (3) WT with DKO cells, and (4) DC-STAMP KO with OC-STAMP KO cells to induce osteoclast or FBGC formation. We evaluated osteoclast and FBGC formation by TRAP and May–Gruenwald Giemsa staining, respectively. Finally, we performed bone morphometric analysis of WT, DC-STAMP KO, OC-STAMP KO, and DKO mice.
  
  Results
  
  Cell–cell fusion occurs normally in co-cultures of DC KO with WT cells, OC KO with WT cells, and DKO with WT cells in both osteoclast and FBGC-inducing conditions. By contrast, co-cultures of DC-STAMP KO with OC-STAMP KO cells did not show cell–cell fusion. Bone morphometric analysis revealed enhanced bone formation in DKO mice.
  
  Conclusion
  
  DC-STAMP and OC-STAMP cooperate to promote osteoclast and FBGC cell–cell fusion. DC-STAMP and OC-STAMP doubly deficient mice exhibit increased osteogenesis.

  • Access to Document (DOI)

• A retrospective analysis of outcomes of non-operative therapy for medication-related osteonecrosis of the jaw

  Kanako Munakata, Hidetaka Miyashita, Yuka Yamada, Tomoya Soma, Seiji Asoda, Taneaki Nakagawa

  Journal of Oral and Maxillofacial Surgery (Elsevier BV)  83 ( 12 ) 1549 - 1559 2025.12

  Accepted,  ISSN  0278-2391

  　View Summary

  Background: Limited research is available regarding the role of nonoperative therapy in managing medication-related osteonecrosis of the jaw (MRONJ) as it relates to progression or resolution of disease. Purpose: The study purpose was to estimate the time to MRONJ stage improvement and risk for relapse among patients managed nonoperatively. Study Design, Setting, Sample: This retrospective cohort study included subjects diagnosed with MRONJ at Keio University Hospital between April 2012 and July 2024. Exclusion criteria included absence of a panoramic radiograph, prior operative therapy, or an observation period of less than 3 months. Predictor Variable: The predictor variable was a set of heterogeneous factors including age, sex, disease stage at the initial visit, presence of diabetes, use of steroid, radiographic findings, primary disease, type of bone-modifying agent (BMA), and BMA holiday before improvement. Disease stage after the stage improvement and BMA holiday after the disease improvement were included as covariates for evaluating the risk of relapse. Main Outcome Variable: The main outcome variable was therapeutic response measured as the time between initial treatment and MRONJ stage improvement, which was defined as an improvement of at least one stage. The secondary outcome was relapse measured as the time between maximal therapeutic response measured by MRONJ stage and worsening of the MRONJ stage. Analyses: The Fine-Gray subdistribution hazard model was used to estimate the cumulative incidence function (CIF) of outcomes, and Gray's test was used to compare CIF curves for relapse after stage improvement. Results: The sample was composed of 118 subjects with a mean age of 73.4 (±10.03), 54 (45.8%) were male, and the median interquartile range (IQR) duration of follow-up was 23 (11 to 32.5) months. During the study interval, 84 (71.2%) subjects achieved stage improvement, resulting in a 12-month CIF of 0.594. After achieving maximal therapeutic effect, 34 subjects (40.5%) experienced relapse. Incomplete healing after the stage improvement was associated with a higher risk of relapse (P = .0016), with a CIF of 0.661 at 36 months. Conclusions and Relevance: More than half of the subjects experienced stage improvement within 12 months. Incomplete healing following initial intervention may increase the risk of relapse.

  • Access to Document (DOI)

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Papers, etc., Registered in KOARA 【 Display / hide 】

Papers, etc., Registered in KOARA 【 Display / hide 】

• Anti-inflammatory mechanisms of action in bone-destroying diseases through inflammatory cytokine regulation

  Soma, Tomoya

  科学研究費補助金研究成果報告書 2023

• ゾレドロネートを投与されたマウスにおける抜歯処置は、炎症性サイトカインを上昇させ、顎骨壊死を誘発する

  Sōma, Tomoya

  (慶應義塾大学大学院医学研究科)  2020

• ゾレドロネートを投与されたマウスにおける抜歯処置は、炎症性サイトカインを上昇させ、顎骨壊死を誘発する

  Sōma, Tomoya

  (慶應義塾大学大学院医学研究科)  2020

• ゾレドロネートを投与されたマウスにおける抜歯処置は、炎症性サイトカインを上昇させ、顎骨壊死を誘発する

  Sōma, Tomoya

  (慶應義塾大学大学院医学研究科)  2020

Reviews, Commentaries, etc. 【 Display / hide 】

Reviews, Commentaries, etc. 【 Display / hide 】

• 当科を受診した歯科治療に起因する縦隔気腫の臨床的検討

  木村 大志, 相馬 智也, 加藤 伸, 小林 夏樹, 莇生田 整治, 角田 和之, 中川 種昭

  日本口腔科学会雑誌 ((NPO)日本口腔科学会)  74 ( 2 ) 75 - 76 2025.07

  ISSN  0029-0297

• 治療抵抗性頭頸部扁平上皮癌を標的とした治療薬の同定

  岡崎 章悟, 吉川 桃子, 相馬 智也, 莇生田 整治, 中島 由梨佳, 今井 健一

  日本歯科医師会雑誌 ((公社)日本歯科医師会)  78 ( 4 ) 384 - 384 2025.07

  ISSN  0047-1763

• 炭酸アパタイトを使用したインプラント周囲炎の再生療法に関する観察研究

  宮下 英高, 堀江 伸行, 森川 曉, 古澤 春佳, 柴崎 竣一, 相馬 智也, 宗像 花楠子, 小高 利絵, 中川 種昭, 莇生田 整治

  顎顔面補綴 ((一社)日本顎顔面補綴学会)  48 ( 1 ) 55 - 55 2025.06

  ISSN  0389-4045

• Immobilization of silver ions on hydroxyapatite-coated titanium using inositol phosphate and its anti-bacterial property

  近藤葵, ZHU X.Y., 鈴木来, 宮下英高, 相馬智也, 那須真奈, 中川種昭, 森川暁, 相澤守

  日本セラミックス協会年会講演予稿集(Web) 2025 2025

• 上顎部動静脈奇形へ経動脈的・経静脈的塞栓術を行った一例

  藤澤昌司, 水谷克洋, 山本洋輔, 塚田実郎, 石川幸之助, 小島光, 莇生田整治, 相馬智也, 秋山武紀, 戸田正博

  日本脳神経血管内治療学会学術集会抄録集(Web) 41st 2025

  ISSN  2759-6907

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Presentations 【 Display / hide 】

Presentations 【 Display / hide 】

• Loading of basic fibroblast growth factor on antibacterial hydroxyapatite-coated titanium substrate and its biological evaluation

  Aoi KONDO, Hidetaka MIYASHITA, Tomoya SOMA, Mana NASU, Taneaki NAKAGAWA, Satoru MORIKAWA, Mamoru AIZAWA

  11th International Congress on Ceramics(ICC’11) (Sapporo Convention Center, Sapporo, Japan) , 

  2026.09

  , 

  Oral presentation (general)

• Determination of adhesive strength between hydroxyapatite-coated titanium and soft tissue using tensile test method

  Aoi Kondo, Shoki Iwama, Hidetaka Miyashita, Tomoya Soma, Mana Nasu, Shunichi Shibazaki, Satoru Morikawa, Mamoru Aizawa

  The 12th International Symposium on Inorganic Phosphate Materials (ISIPM-12) (Meiji University, Surugadai Campus, Tokyo, Japan) , 

  2026.08

  , 

  Poster presentation

• Ag+コーティングスクリュー型インプラントは、マウスモデルにおいてインプラント周囲炎を抑制する

  相馬智也, 那須真奈, 宮下英高, 安居孝純, 本間風花, 鈴木来, 宮本健史, 相澤守, 森川暁

  [Domestic presentation]  第11回日本骨免疫学会 (沖縄県 石垣市 ANAインターコンチネンタル石垣) , 

  2026.06

  , 

  Poster presentation

• In vivo response of β-tricalcium phosphate-based paste-like artificial bone with antibacterial property under potentially-infectious conditions using rabbit model

  Hidetaka Miyashita, Yuki Kamaya, Kitaru Suzuki, Shiori Kato, Tomoya Soma, Mana Nasu, Kanako Munakata, Taneaki Nakagawa, Mamoru Aizawa, Satoru Morikawa

  6th Japanese-German Goethe Symposium in Cranio-Maxillofacial Surgery, 

  2026.06

• 腹部大動脈瘤ステント留置患者の慢性DICに起因した抜歯後出血の1例

  磐田翔, 相馬智也, 木村大志, 宗像花楠子, 山田有佳, 宮下英高, 莇生田整治

  [Domestic presentation]  第221回（公社）日本口腔外科学会関東支部学術集会 (東京都 東京歯科大学水道橋キャンパス) , 

  2026.05

  , 

  Oral presentation (general)

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Research Projects of Competitive Funds, etc. 【 Display / hide 】

Research Projects of Competitive Funds, etc. 【 Display / hide 】

• Elucidation of the Regulatory Mechanisms of Osteoclast Fusion Factors DC-STAMP/OC-STAMP

  2026.04

  -

  2029.03

  日本学術振興会, Grants-in-Aid for Scientific Research, Grant-in-Aid for Early-Career Scientists, Principal investigator

  　View Summary

  口腔顎顔面外科学の領域では、口腔疾患の多くに骨破壊・骨吸収などを伴う炎症性疾患が多く存在している。申請者の研究室では、これまでの研究において、樹状細胞特異的膜貫通蛋白質(以下：DC-STAMP)や破骨細胞刺激膜貫通蛋白質(OC-STAMP)といった破骨細胞融合に必須である分子に着目することで、破骨細胞融合制御機構の解明を継続的かつ精力的に行ってきた。本研究では、前段階の実験で作成することに成功したDC-STAMP, OC-STAMP ダブルノックアウトマウスを使用することにより、細胞融合メカニズムを解明することを目的とし、最終的には治療のターゲットとなる因子の決定を行いたい。

• Mechanisms of Differentiation Suppression in Oral Squamous Cell Carcinoma Driven by the Oral Microenvironment and Identification of Therapeutic Targets

  2026.04

  -

  2029.03

  Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, Grant-in-Aid for Scientific Research (C), Coinvestigator(s)

  　View Summary

  口腔扁平上皮癌は角化を伴う分化傾向を示し、その分化度は悪性度や治療抵抗性に関わる重要な病理学的指標であるが、分化制御機構、とくに局所微小環境の影響は十分に解明されていない。申請者は口腔扁平上皮癌細胞を皮下および舌に移植し、舌では腫瘍成長が促進されるとともに、分化マーカーKRT10陽性細胞が減少し、未分化細胞割合が増加することを見出した。一方、Ki67陽性率に差はなく、口腔微小環境による分化抑制が腫瘍進展に寄与することが示唆された。本研究では、その分子基盤を解明し、新規治療標的探索につなげる。

• 力学的負荷を加えた多重障害インプラント周囲炎モデルの構築

  2024.10

  -

  2025.10

  公益社団法人日本顎顔面インプラント学会 , 第3回赤坂庸子若手研究奨励基金, Coinvestigator(s)

• 進行口腔扁平上皮癌に対するPCE導入化学療法による縮小手術の可能性についての検討

  2023.06

  -

  2024.08

  公益社団法人 日本口腔外科学会, 2022・2023年度研究助成「次世代若手臨床研究推進プロジェクト」, Coinvestigator(s)

• ビタミンD誘導体による難治性骨破壊性疾患の治療への応用

  2023.04

  -

  2026.03

  日本学術振興会, Grants-in-Aid for Scientific Research, Grant-in-Aid for Early-Career Scientists, Principal investigator

  　View Summary

  口腔顎顔面外科領域では口腔内疾患の多くに骨吸収や骨破壊などを伴う炎症性疾患が多く認められる。ビスフォスフォネート製剤などによる骨吸収製剤の副作用である薬剤関連顎骨壊死も炎症を伴う骨破壊性疾患のひとつである。申請者はこれまで、ビスフォスフォネート製剤を投与したマウスモデルを用い、炎症性サイトカインが、骨壊死の発生や破骨細胞を介した骨破壊を引き起こすことを明らかにした。近年、ビタミンDの抗炎症作用が注目されており、そこで本研究では、炎症を伴う難治性骨破壊性疾患に対するビタミンDの分子メカニズムを解明し、新たな治療方法の確立を目指したい。

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Awards 【 Display / hide 】

Awards 【 Display / hide 】

• JBMM Excellent Paper Award

  Tomoya Soma, Ryotaro Iwasaki, Yuiko Sato, Tami Kobayashi, Satoshi Nakamura, Yosuke Kaneko, Eri Ito, Hiroyuki Okada, Hisato Watanabe, Kana Miyamoto, Morio Matsumoto, Masaya Nakamura, Seiji Asoda, Hiromasa Kawana, Taneaki Nakagawa, Takeshi Miyamoto, 2024.07, The Japanese Society for Bone and Mineral Research, Tooth extraction in mice administered zoledronate increases inflammatory cytokine levels and promotes osteonecrosis of the jaw

  Type of Award： Award from Japanese society, conference, symposium, etc.

• 第75回日本口腔科学会学術集会 Rising Scientist賞

  相馬智也, 森田麻友, 岩崎良太郎, 莇生田整治, 河奈裕正, 中川種昭, 宮本健史, 2021.05, ゾレドロネート投与と侵襲的歯科処置は，炎症性サイトカインを上昇させ，骨吸収薬剤関連顎骨壊死を誘発する

  Type of Award： Award from Japanese society, conference, symposium, etc.

• 第5回日本骨免疫学会 優秀演題賞

  相馬智也, 森田麻友, 岩崎良太郎, 中川種昭, 宮本健史, 2019.06, 骨吸収抑制薬による薬剤関連顎骨壊死には炎症性サイトカインの上昇が必須である

  Type of Award： Award from Japanese society, conference, symposium, etc.

• 日本歯科医学会ポスター賞（若手研究者部門）

  岡﨑章悟, 吉川桃子, 相馬智也, 莇生田整治, 中島由梨佳, 今井健一, 2025.09, 第25回日本歯科医学会学術大会, 治療抵抗性頭頸部扁平上皮癌を標的とした治療薬の同定

  Type of Award： Award from Japanese society, conference, symposium, etc.

• 第36回日本小児口腔外科学会優秀発表賞（ポスター発表）

  永田香織, 臼田慎, 二宮真希, 長嶺宏樹, 佐藤晃子, 赤田晋也, 遠藤友樹, 相馬智也, 莇生田整治, 木津英樹, 2024.11, 第36回日本小児口腔外科学会総会・学術大会, 小児萌出遅延歯に対する開窓・牽引療法の検討

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Memberships in Academic Societies 【 Display / hide 】

Memberships in Academic Societies 【 Display / hide 】

• Sigma Xi (Scientific Research Honor Society), Full Membership, 

  2026.06

  -

  Present

• Asian Association of Oral and Maxillofacial Surgeons, 

  2018.01

  -

  Present

• Japanese Society of Oral and Maxillofacial Surgeons, 

  2009.08

  -

  Present

• Japan Society for Head and Neck Cancer, 

  2026.02

  -

  Present

• Japanese Society of Pediatric Oral and Maxillofacial Surgery, 

  2022.09

  -

  Present

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