Development of "Imaging Biomarker" cell sorter system for identification of CTCs

2021 Fiscal Year Final Research Report

• Project/Area Number: 17H02757
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Nano/Microsystems
• Research Institution: Waseda University
• Principal Investigator: YASUDA Kenji 早稲田大学, 理工学術院, 教授 (20313158)
• Project Period (FY): 2017-04-01 – 2022-03-31
• Keywords: ナノマイクロバイオシステム / 血中がん細胞

Outline of Final Research Achievements

We examined the distribution of circulating tumor cell (CTC) clusters in blood over time using an on-chip multi-imaging flow cytometry system, which can obtain morphometric parameters of cells and those clusters as “imaging biomarkers”. Both bright-field (BF) and fluorescent (FL) images were acquired within the intervals for real-time cell sorting. A GFP-transfected prostate cancer cell line was implanted into Copenhagen rats, and the blood samples were collected 2 to 11 days later and measured. The results showed that cells having larger BF area increased in number seven days after the cancer cell implantation, as confirmed by FL measurements, and they constituted more than 1% of all white blood cells. These results indicate that the mapping of cell size distribution is useful for identifying an increase of irregular cells such as cell clusters in blood, and show that CTC clusters become more abundant in blood over time after malignant tumor formation.

Free Research Field

生物物理学

Academic Significance and Societal Importance of the Research Achievements

末梢循環がん細胞（circulating tumor cell: CTC）は、がん患者の末梢血から発見され、転移がんの原因と考えられている。近年、CTCの検出技術の開発が急速に進み、血中での濃度が非常に低いCTCを検出するために、すでに５０種類を超える手法が開発されているが、がん細胞の普遍的なバイオマーカーが存在しないことが大きな障壁となっている。本研究の成果は、血中の細胞塊はがん細胞などの異常細胞であるというユニークな視点で無染色で血中の細胞塊を同定して回収する技術の開発であり、その成果は転移がんのより正確な病理検査を実現することが期待される。