Ph.D, Hokkaido University

Osmotic pressure

Ploidy

Collective invasion

Collective migration

Morphognesis

3D cell culture

Life Science, Molecular biology

Life Science, Cell biology

Bachelor's degree program, School of Science

Master's degree program, Graduate School of Life Science

Doctoral (PhD) degree program, Graduate School of Life Science

Mar. 2021, 北海道大学, 北海道大学大塚賞

Mar. 2021, 日本生物物理学会北海道支部, 支部例会発表賞
浸透圧勾配が引き起こす上皮細胞シートのドーム形成

May 2014, 日本学生支援機構, 第一種奨学生「特に優れた業績による返還全額免除」

Profiling cell proliferation after whole-genome duplication in human cells
Guang Yang; Masaya Inoko; Kaito Ogura; Sumire Ishida-Ishihara; Yuki Tsukada; Akira Funahashi; Masanao Sato; Ryota Uehara
openRxiv, 13 Mar. 2026
Abstract

Though whole-genome duplication (WGD) contributes to cancer progression, the mechanism of post-WGD cell proliferation remains unclear. Here, using 6-day live-imaging, we analyzed the proliferation dynamics of more than 150 post-WGD HCT116 cell lineages. A quantitative comparison of mitotic patterns and cell fates between proliferative and non-proliferative lineages revealed that multipolar chromosome segregation in early mitosis is a key factor limiting the proliferative capacity of post-WGD progenies. Multipolar chromosome segregation suppressed post-WGD cell viability, particularly when accompanied by drastic chromosome loss or when it repeatedly occurred. Tracing proliferative lineages elucidated that they proliferated mainly by imposing the risk of multipolar chromosome segregation on one of two sub-lineages that formed after the first bipolar division. Meanwhile, a considerable proportion of proliferative lineages consisted entirely of progeny of early multipolar chromosome segregation events. Our results highlight key cellular events that determine the proliferation dynamics and diversity of post-WGD progenies, providing a fundamental reference for understanding WGD-associated bioprocesses.

Summary statement

Live image tracing of >150 cell lineages reveals the cross-generation dynamics of multipolar chromosome segregation that determine the fates of post-whole-genome duplication progeny cells.

Fragility of ER homeostatic regulation underlies haploid instability in human somatic cells.
Sumire Ishida-Ishihara; Kan Yaguchi; Sena Miura; Ryoto Nomura; QiJiao Wang; Koya Yoshizawa; Kimino Sato; Guang Yang; Krisztina Veszelyi; Gabor Banhegyi; Eva Margittai; Ryota Uehara
The Journal of biological chemistry, 107909, 107909, 19 Oct. 2024, [Peer-reviewed], [Lead author], [International Magazine]
English, Scientific journal, Mammalian somatic cells are generally unstable in the haploid state, resulting in haploid-to-diploid conversion within a short time frame. However, cellular and molecular principles that limit the sustainability of somatic haploidy remain unknown. In this study, we found the haploidy-linked vulnerability to ER stress as a critical cause of haploid intolerance in human somatic cells. Pharmacological induction of ER stress selectively induced apoptosis in haploid cells, facilitating the replacement of haploids by co-existing diploidized cells in a caspase-dependent manner. Biochemical analyses revealed that unfolded protein response (UPR) was activated with similar dynamics between haploids and diploids upon ER stress induction. However, haploids were less efficient in solving proteotoxic stress, resulting in a bias toward a proapoptotic mode of UPR signaling. Artificial replenishment of chaperone function substantially alleviated the haploidy-linked upregulation of proapoptotic signaling and improved haploid cell retention under tunicamycin-induced ER stress. These data demonstrate that the ER stress-driven haploid instability stems from inefficient proteostatic control that alters the functionality of UPR to cause apoptosis selectively in haploids. Interestingly, haploids suffered a higher level of protein aggregation even in unperturbed conditions, and the long-term stability of the haploid state was significantly improved by alleviating their natural proteotoxicity. Based on these results, we propose that the haploidy-specific vulnerability to ER stress creates a fundamental cause of haploid intolerance in mammalian somatic cells. Our findings provide new insight into the principle that places a stringent restriction on the evolution of animal life cycles.

Caging Bioactive Triarylimidazoles: An Approach to Create Visible Light-Activatable Drugs
Jiajun Qi; Ammathnadu S. Amrutha; Sumire Ishida-Ishihara; Hisham M. Dokainish; P. K. Hashim; Ryu Miyazaki; Masumi Tsuda; Shinya Tanaka; Nobuyuki Tamaoki
Journal of the American Chemical Society, 146, 26, 18002, 18010, American Chemical Society (ACS), 21 Jun. 2024, [Peer-reviewed]
Scientific journal

Tetraploidy‐linked sensitization to CENP‐E inhibition in human cells
Koya Yoshizawa; Akira Matsura; Masaya Shimada; Sumire Ishida‐Ishihara; Fuyu Sato; Takahiro Yamamoto; Kan Yaguchi; Eiji Kawamoto; Taruho Kuroda; Kazuya Matsuo; Nobuyuki Tamaoki; Ryuichi Sakai; Yasuhito Shimada; Mithilesh Mishra; Ryota Uehara
Molecular Oncology, 17, 6, 1148, 1166, Wiley, 11 Feb. 2023, [Peer-reviewed]
Scientific journal, Tetraploidy is a hallmark of cancer cells, and tetraploidy‐selective cell growth suppression is a potential strategy for targeted cancer therapy. However, how tetraploid cells differ from normal diploids in their sensitivity to anti‐proliferative treatments remains largely unknown. In this study, we found that tetraploid cells are significantly more susceptible to inhibitors of a mitotic kinesin (CENP‐E) than are diploids. Treatment with a CENP‐E inhibitor preferentially diminished the tetraploid cell population in a diploid–tetraploid co‐culture at optimum conditions. Live imaging revealed that a tetraploidy‐linked increase in unsolvable chromosome misalignment caused substantially longer mitotic delay in tetraploids than in diploids upon moderate CENP‐E inhibition. This time gap of mitotic arrest resulted in cohesion fatigue and subsequent cell death, specifically in tetraploids, leading to tetraploidy‐selective cell growth suppression. In contrast, the microtubule‐stabilizing compound paclitaxel caused tetraploidy‐selective suppression through the aggravation of spindle multipolarization. We also found that treatment with a CENP‐E inhibitor had superior generality to paclitaxel in its tetraploidy selectivity across a broader spectrum of cell lines. Our results highlight the unique properties of CENP‐E inhibitors in tetraploidy‐selective suppression and their potential use in the development of tetraploidy‐targeting interventions in cancer.

Improvement of the cell viability of hepatocytes cultured in three-dimensional collagen gels using pump-free perfusion driven by water level difference.
Sumire Ishida-Ishihara; Ryota Takada; Kazuya Furusawa; Seiichiro Ishihara; Hisashi Haga
Scientific reports, 12, 1, 20269, 20269, 24 Nov. 2022, [Peer-reviewed], [Lead author], [International Magazine]
English, Scientific journal, Cell-containing collagen gels are one of the materials employed in tissue engineering and drug testing. A collagen gel is a useful three-dimensional (3D) scaffold that improves various cell functions compared to traditional two-dimensional plastic substrates. However, owing to poor nutrient availability, cells are not viable in thick collagen gels. Perfusion is an effective method for supplying nutrients to the gel. In this study, we maintained hepatocytes embedded in a 3D collagen gel using a simple pump-free perfusion cell culture system with ordinary cell culture products. Flow was generated by the difference in water level in the culture medium. Hepatocytes were found to be viable in a collagen gel of thickness 3.26 (± 0.16 S.E.)-mm for 3 days. In addition, hepatocytes had improved proliferation and gene expression related to liver function in a 3D collagen gel compared to a 2D culture dish. These findings indicate that our perfusion method is useful for investigating the cellular functions of 3D hydrogels.

浸透圧勾配による上皮細胞シート及び細胞外マトリクスの三次元形態形成
石原すみれ; 芳賀永
生化学, 94, 6, 896, 900, 2022, [Invited], [Lead author]

Osmotic gradients induce stable dome morphogenesis on extracellular matrix.
S. Ishida-Ishihara; M. Akiyama; K. Furusawa; I. Naguro; H. Ryuno; T. Sushida; S. Ishihara; H. Haga
Journal of Cell Science, 133, 14, 2020, [Peer-reviewed], [Lead author], [International Magazine]
English, Scientific journal, One of the fundamental processes in morphogenesis is dome formation, but many of the mechanisms involved are unexplored. Previous in vitro studies showed that an osmotic gradient is the driving factor of dome formation. However, these investigations were performed without extracellular matrix (ECM), which provides structural support to morphogenesis. With the use of ECM, we observed that basal hypertonic stress induced stable domes in vitro that have not been seen in previous studies. These domes developed as a result of ECM swelling via aquaporin water transport activity. Based on computer simulation, uneven swelling, with a positive feedback between cell stretching and enhanced water transport, was a cause of dome formation. These results indicate that osmotic gradients induce dome morphogenesis via both enhanced water transport activity and subsequent ECM swelling.

The intercellular expression of type-XVII collagen, laminin-332, and integrin-β1 promote contact following during the collective invasion of a cancer cell population.
Y. Kumagai; J. Nio-Kobayashi; S. Ishida-Ishihara; H. Tachibana; R. Omori; A. Enomoto; S. Ishihara; H. Haga
Biochemical and Biophysical Research Communications, 514, 4, 1115, 1121, 2019, [Peer-reviewed], [International Magazine]
English, Scientific journal, Cancer cells can invade as a population in various cancer tissues. This phenomenon is called collective invasion, which is associated with the metastatic potential and prognosis of cancer patients. The collectiveness of cancer cells is necessary for collective invasion. However, the mechanism underlying the generation of collectiveness by cancer cells is not well known. In this study, the phenomenon of contact following, where neighboring cells move in the same direction via intercellular adhesion, was investigated. An experimental system was created to observe the two-dimensional invasion using a collagen gel overlay to study contact following in collective invasion. The role of integrin-β1, one of the major extracellular matrix (ECM) receptors, in contact following was examined through the experimental system. Integrin-β1 was localized to the intercellular site in squamous carcinoma cells. Moreover, the intercellular adhesion and contact following were suppressed by treatment of an integrin-β1 inhibitory antibody. ECM proteins such as laminin-332 and type-XVII collagen were also localized to the intercellular site and critical for contact following. Collectively, it was demonstrated that the activity of integrin-β1 and expression of ECM proteins in the intercellular site promote contact following in the collective invasion of a cancer cell population.

Girdin/GIV regulates collective cancer cell migration by controlling cell adhesion and cytoskeletal organization
X. Wang; A. Enomoto; L.Weng; Y. Mizutani; S. Abudureyimu; N. Esaki; Y. Tsuyuki; C. Chen; S. Mii; N. Asai; H. Haga; S. Ishida; K. Yokota; M. Akiyama; M. Takahashi
Cancer Science, 109, 11, 3643, 3656, 2018, [Peer-reviewed], [International Magazine]
English, Scientific journal, Pathological observations show that cancer cells frequently invade the surrounding stroma in collective groups rather than through single cell migration. Here, we studied the role of the actin-binding protein Girdin, a specific regulator of collective migration of neuroblasts in the brain, in collective cancer cell migration. We found that Girdin was essential for the collective migration of the skin cancer cell line A431 on collagen gels as well as their fibroblast-led collective invasion in an organotypic culture model. We provide evidence that Girdin binds to β-catenin that plays important roles in the Wnt signaling pathway and in E-cadherin-mediated cell-cell adhesion. Girdin-depleted cells displayed scattering and impaired E-cadherin-specific cell-cell adhesion. Importantly, Girdin depletion led to impaired cytoskeletal association of the β-catenin complex, which was accompanied by changes in the supracellular actin cytoskeletal organization of cancer cell cohorts on collagen gels. Although the underlying mechanism is unclear, this observation is consistent with the established role of the actin cytoskeletal system and cell-cell adhesion in the collective behavior of cells. Finally, we showed the correlation of the expression of Girdin with that of the components of the E-cadherin complex and the differentiation of human skin cancer. Collectively, our results suggest that Girdin is an important modulator of the collective behavior of cancer cells.

Mathematical model of collective cell migrations based on cell polarity.
M. Akiyama; T. Sushida; S. Ishida; H. Haga
Development, Growth & Differentiation, 59, 5, 471, 490, 2017, [Peer-reviewed]

TRIM27/MRTF-B-dependent integrin β1 expression defines leading cells in cancer cell collectives.
T. Kato; A. Enomoto; T. Watanabe; H. Haga; S. Ishida; Y. Kondo; K. Furukawa; S. Mii; L. Weng; M. Ishida-Takagishi; M. Asai; N. Asai; K. Kaibuchi; Y. Murakumo; M. Takahashi
Cell Reports, 7, 1, 12, 2014, [Peer-reviewed]

Epithelial Sheet Folding Induces Lumen Formation by Madin-Darby Canine Kidney Cells in a Collagen Gel
Ishida Sumire; Tanaka Ryosuke; Yamaguchi Naoya; Ogata Genki; Mizutani Takeomi; Kawabata Kazushige; Haga Hisashi
PLOS ONE, 9, 8, e99655, Public Library of Science, 2014, [Peer-reviewed], [Lead author]
English, Lumen formation is important for morphogenesis; however, an unanswered question is whether it involves the collective migration of epithelial cells. Here, using a collagen gel overlay culture method, we show that Madin-Darby canine kidney cells migrated collectively and formed a luminal structure in a collagen gel. Immediately after the collagen gel overlay, an epithelial sheet folded from the periphery, migrated inwardly, and formed a luminal structure. The inhibition of integrin-beta 1 or Rac1 activity decreased the migration rate of the peripheral cells after the sheets folded. Moreover, lumen formation was perturbed by disruption of apical-basolateral polarity induced by transforming growth factor-beta 1. These results indicate that cell migration and cell polarity play an important role in folding. To further explore epithelial sheet folding, we developed a computer-simulated mechanical model based on the rigidity of the extracellular matrix. It indicated a soft substrate is required for the folding movement.

浸透圧勾配による上皮細胞シート及び細胞外マトリクスの三次元形態形成
石原すみれ; 芳賀永
生化学 第９４巻第６号、pp. 896-900, 2022

ゲル基質上の上皮細胞シートが引き起こす浸透圧依存的なドーム形成
石原(石田) すみれ; 秋山 正和; 須志田 隆道; 古澤 和也; 名黒 功; 立野 浩輝; 石原 誠一郎; 芳賀 永
第56回日本生化学会北海道支部・東北支部／日本生物物理学会北海道支部 合同シンポジウム, Jul. 2019, Invited oral presentation
[Invited]

国際研究集会企画プログラム, 2024年, 博士後期課程, 生命科学院

細胞構造科学Ⅲ, 2024年, 学士課程, 理学部

高分子機能学基礎実験, 2024年, 学士課程, 理学部

がんの不均一性構築における染色体倍加の寄与の解明
Apr. 2026 - Mar. 2027
日本学術振興会 科学研究費助成事業, 若手研究, Principal investigator

Evolution of malignant tumors starting from polyploid giant cancer cells
Grants-in-Aid for Scientific Research
Oct. 2022 - Mar. 2027
田守 洋一郎; 榎本 篤; 石原 すみれ
これまでの研究から、ショウジョウバエの翅原基上皮組織に誘導したがん原性変異細胞（極性形成に関わるlglもしくはscribbleの変異とがん原遺伝子Rasの活性化の二重変異）からなる腫瘍が、基底膜を破って間質側に侵入すると、非常に高い確率で巨核を持った細胞が数多く出現することを観察していた。一方、FACSによるDNA量解析や、共焦点顕微鏡によるイメージングベースの倍数性解析によって徹底的な検証を行ったところ、これら大部分の浸潤性腫瘍細胞は２倍体を維持しており、ごく少数の細胞だけが多倍体化していることが分かってきた。この観察結果は当初の仮説とは異なるものであるが、実際の浸潤性のがん組織内に存在する多倍体化細胞も少数であるため、多倍体がん細胞のモデルとしては、より実際の状況の再現性が高いモデルということができる。
この腫瘍モデルに対してさらに行なった解析において、間質側へ侵入した腫瘍では、大部分の細胞でクロマチンの状態に大きな変化が起こっていることが分かってきた。具体的には、DAPIを用いたDNA染色で、浸潤性腫瘍内の大部分の細胞で核自体のサイズは大きくなっているものの、多くの細胞でヘテロクロマチン領域と考えられる部分は増加しており、その他の領域が核内で分散している様子が確認された。これらの浸潤性腫瘍細胞モデルにおけるクロマチン状態と倍数性の変化の基本的な観察結果について、代表者自ら遺伝研研究会として企画および主宰を行なった「倍数性研究会」を含め、国内外の複数の学会で発表した。さらに、これらの基礎データを含めた英文総説を発表した。
また、浸潤性腫瘍の大部分の細胞でクロマチン状態が変化していることから、これに関係する因子を探るために、今年度は一細胞レベルでのエピゲノム解析（scATAC-seq）を実施した。
Japan Society for the Promotion of Science, Fund for the Promotion of Joint International Research (Fostering Joint International Research (B)), Kyoto University, Coinvestigator, 22KK0110

がん細胞集団における染色体倍加を介した低酸素順応機構の解明
2025年度 研究助成金
Jul. 2025 - Mar. 2026
石原すみれ
公益財団法人 秋山記念生命科学振興財団, Principal investigator

染色体倍加によるがん細胞集団の悪性化機構
科学研究費助成事業
Aug. 2023 - Mar. 2026
石原 すみれ
細胞のもつ染色体コピー数が正常値(二倍体状態)から倍増する「染色体倍加」現象は、 固形がんの30%超に共通してみられる異常で、予後不良と強く相関する。染色体倍加は、マウスを用いた個体レベルの移植実験で腫瘍形成や転移を顕著に亢進することから、がん病態の主要因の一つと考えられている。また、培養細胞を用いた一細胞レベルの実験から、染色体倍加はゲノム不安定性や代謝変化を通して細胞形質を劇的に変化することが示唆されている。このような一細胞レベルの変化は、細胞集団の三次元構造や機能に作用してがん病態を引き起こすことが推察されるが、「一細胞レベル」と「個体レベル」の間にあたる「細胞集団レベル」で染色体倍加が与える影響についての知見は極めて乏しい。「細胞集団レベル」における染色体倍加の影響を調べるため、研究目的にあげた「倍加細胞混合スフェロイドの形態観察」「倍加細胞で接着能を増大させる責任因子の特定」を行った。
二倍体細胞と染色体倍加細胞において、ハンギングドロップ法によるスフェロイド形成を行なった。スフェロイドあたりの細胞数を減少させたところ、二倍体のみの場合よりも倍加細胞を混合した場合の方が、スフェロイドの形成能が向上することを見出した。また、この時、倍加細胞はスフェロイド中心部に集積することを発見した。現在は、スフェロイドの形成能向上における倍加細胞の中心部への集積の意義を探索するとともに、スフェロイドの形成能が向上する責任因子を次世代シークエンサーを用いた遺伝子発現解析や接着タンパク質のウェスタンブロット実験を用いて探索中である。
日本学術振興会, 研究活動スタート支援, 北海道大学, Principal investigator, 23K19360

「液体」上で細胞を飼う：器官構築の根幹に迫る新規アプローチ
Grants-in-Aid for Scientific Research Grant-in-Aid for JSPS Fellows
Apr. 2017 - Mar. 2019
石原(石田)すみれ; 石田 すみれ
動物の複雑な体構造は，上皮組織の座屈や折りたたみ・伸長といった単純な変形が組み合わされることにより形成される．ドーム形成は上皮組織の折りたたみのひとつであるが，ドーム形成を引き起こす要因はほとんど分かっていない．先行研究により浸透圧勾配が要因として提唱されているものの，その直接的証拠は報告されていない．そこで我々は浸透圧勾配によってドーム形成が誘引されるかとその仕組みとをインビトロで調べた．
本研究では，液体培養基質であるマトリゲルをゲニピンという架橋剤で処理して使用した．このゲニピン処理マトリゲル（以下，GPM）上の上皮細胞シートへ浸透圧勾配を与えると，細胞シートは内部がGPMで満たされたドームへと変形した．
次に，浸透圧勾配がGPM上でドーム形成を起こす仕組みを調べた．3Dライブイメージングの結果，ドーム形成時にはGPMが膨潤していることがわかった．ゲルは内部の溶液の塩濃度によって膨潤度が変わる．また，細胞の水チャネル・アクアポリン（AQP）は水を高張側に輸送する．そのため，ドーム形成時もAQPによって水がGPMへと輸送されてGPM中の塩濃度が下がり、膨潤が起こっている可能性がある．この可能性を検証するため，AQP阻害剤を投与した．その結果，膨潤が抑制されドームもできなかった．
さらに我々は，ドーム構造の力学的機序を調べた．ミオシンはリン酸化により細胞内張力を発生させる．このミオシンの阻害剤（ブレビスタチン, Y27632）を投与したところ，ドーム形成が阻害された．現在は，細胞内張力の局在を調べるため，リン酸化ミオシンの免疫蛍光染色に取り組んでいる．
これらの事実は，浸透圧勾配によってGPM上の細胞シートにドーム形成が誘引されることを示した重要な結果である．今後は，細胞内張力の局在明らかにし，来年度中に成果を論文にまとめる予定である．
Japan Society for the Promotion of Science, Grant-in-Aid for JSPS Fellows, Hokkaido University, 17J06276

科学の芽を育む実験教室
北大元気プロジェクト
2011 - 2012
北海道大学

細胞の培養⽅法、細胞の培養⽅法を⽤いたクリーニング⽅法、 培養装置及び 培養キット
Patent right
特願2022-011768