Development of a biomarker for bone metastasis of breast cancer by serum exosome analysis

2021 Fiscal Year Final Research Report

• Project/Area Number: 20K16426
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 50020:Tumor diagnostics and therapeutics-related
• Research Institution: Tokyo Medical University
• Principal Investigator: MIYAHARA KANA 東京医科大学, 医学部, 講師 (90532391)
• Project Period (FY): 2020-04-01 – 2022-03-31
• Keywords: 乳癌 / 骨転移 / エクソソーム / バイオマーカー / マイクロRNA

Outline of Final Research Achievements

Three cohorts of patients with luminal breast cancer were enrolled in the study: (1) postoperative recurrence-free patients (10 cases), (2) patients with breast cancer with bone metastasis alone (11 cases), and (3) patients with distant metastasis other than bone (11 cases). MicroRNAs in serum exosomes were extracted, and microRNA expression was comprehensively analyzed using a next-generation sequencer (NGS) and compared between cohorts. Hierarchical clustering analysis of total microRNA expression showed that the samples in the same cohort were similar and there were differences between cohorts. Next, the expression of each miRNA was compared between cohorts to determine whether any miRNAs were significantly expressed in bone metastases, and 10 microRNAs were identified that were significantly expressed in the bone alone metastasis cohort.

Free Research Field

乳癌

Academic Significance and Societal Importance of the Research Achievements

乳癌で最も頻度の高い遠隔転移である骨転移は、疼痛、骨折など様々な骨関連事象を引き起こし、QOLを著しく低下させる。骨転移に伴う、生命予後の増悪およびQOLの低下を解決するためには、早期に骨転移を発見することや予防することが臨床上重要である。そのためには、乳癌骨転移のバイオマーカーを開発することが不可欠であると考え、本研究では乳癌骨転移のバイオマーカーの開発を目指した。本研究のように血液検査で骨転移のリスクまたは早期発見が可能になれば、非常に低侵襲な検査であり、なおかつ、予防もしくは早期治療の介入が可能となり臨床的メリットは極めて大きい。