Updated on 2022/12/04


ADACHI, Chihiro
Scopus Paper Info  
Paper Count: 0  Citation Count: 0  h-index: 2

Citation count denotes the number of citations in papers published for a particular year.

Faculty of Science and Engineering, School of Advanced Science and Engineering
Job title
Assistant Professor(without tenure)


  • 2018.04

    早稲田大学   先進理工学研究科   生命医科学専攻  


  • 2016.04

    早稲田大学   先進理工学研究科   生命医科学専攻  


  • 2012.04

    早稲田大学   先進理工学部   生命医科学科  

Research Experience

  • 2021.04

    Waseda University   School of Advanced Science and Engineering   Assistant professor

  • 2020.04

    早稲田大学   先進理工学部   助手


Research Areas

  • Neuroscience-general

Research Interests

  • Calcium signal

  • Astrocyte


  • Proliferative Classification of Intracranially Injected HER2-positive Breast Cancer Cell Lines

    Yuka Kuroiwa, Jun Nakayama, Chihiro Adachi, Takafumi Inoue, Shinya Watanabe, Kentaro Semba

    Cancers   12 ( 7 ) 1811 - 1811  2020.07  [Refereed]

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    HER2 is overexpressed in 25–30% of breast cancers, and approximately 30% of HER2-positive breast cancers metastasize to the brain. Although the incidence of brain metastasis in HER2-positive breast cancer is high, previous studies have been mainly based on cell lines of the triple-negative subtype, and the molecular mechanisms of brain metastasis in HER2-positive breast cancer are unclear. In the present study, we performed intracranial injection using nine HER2-positive breast cancer cell lines to evaluate their proliferative activity in brain tissue. Our results show that UACC-893 and MDA-MB-453 cells rapidly proliferated in the brain parenchyma, while the other seven cell lines moderately or slowly proliferated. Among these nine cell lines, the proliferative activity in brain tissue was not correlated with either the HER2 level or the HER2 phosphorylation status. To extract signature genes associated with brain colonization, we conducted microarray analysis and found that these two cell lines shared 138 gene expression patterns. Moreover, some of these genes were correlated with poor prognosis in HER2-positive breast cancer patients. Our findings might be helpful for further studying brain metastasis in HER2-positive breast cancer.



  • Sonic hedgehog enhances calcium oscillations in hippocampal astrocytes

    Chihiro Adachi, Naoto Kakinuma, Soo Hyun Jo, Takayuki Ishii, Yusuke Arai, Satoshi Arai, Tetsuya Kitaguchi, Sen Takeda, Takafumi Inoue

    Journal of Biological Chemistry   294 ( 44 ) 16034 - 16048  2019.09  [Refereed]

    Authorship:Lead author

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    Sonic hedgehog (SHH) is important for organogenesis during development. Recent studies have indicated that SHH is also involved in the proliferation and transformation of astrocytes to the reactive phenotype. However, the mechanisms underlying these are unknown. Involvement of SHH signaling in calcium (Ca) signaling has not been extensively studied. Here, we report that SHH and Smoothened agonist (SAG), an activator of the signaling receptor Smoothened (SMO) in the SHH pathway, activate Ca oscillations in cultured murine hippocampal astrocytes. The response was rapid, on a minute time scale, indicating a noncanonical pathway activity. Pertussis toxin blocked the SAG effect, indicating an involvement of a G(i) coupled to SMO. Depletion of extracellular ATP by apyrase, an ATP-degrading enzyme, inhibited the SAG-mediated activation of Ca oscillations. These results indicate that SAG increases extracellular ATP levels by activating ATP release from astrocytes, resulting in Ca oscillation activation. We hypothesize that SHH activates SMO-coupled Gi in astrocytes, causing ATP release and activation of G(q/11)-coupled P2 receptors on the same cell or surrounding astrocytes. Transcription factor activities are often modulated by Ca patterns; therefore, SHH signaling may trigger changes in astrocytes by activating Ca oscillations. This enhancement of Ca oscillations by SHH signaling may occur in astrocytes in the brain in vivo because we also observed it in hippocampal brain slices. In summary, SHH and SAG enhance Ca oscillations in hippocampal astrocytes, G(i) mediates SAG-induced Ca oscillations downstream of SMO, and ATP-permeable channels may promote the ATP release that activates Ca oscillations in astrocytes.



  • 脳組織中での増殖能に基づくHER2陽性乳がん細胞株の分類

    黒岩由佳, 黒岩由佳, 中山淳, 中山淳, 足立ちひろ, 井上貴文, 山本雄介, 渡辺慎哉, 仙波憲太郎, 仙波憲太郎

    日本分子生物学会年会プログラム・要旨集(Web)   43rd  2020


Specific Research

  • 脳内へのコレステロール蓄積量評価系の構築


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  • アストロサイトでのコレステロール誘導性カルシウム振動が細胞生存へ果たす意味


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  • アストロサイトにおけるコレステロール誘導性カルシウム振動の機構解明


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