Identification of circulating tumor stem cells in the peripheral blood of gastrointestinal cancers using cancer stem cell markers and their clinical utility.

2022 Fiscal Year Final Research Report

• Project/Area Number: 20K17676
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 55020:Digestive surgery-related
• Research Institution: University of Toyama
• Principal Investigator: Watanabe Toru 富山大学, 学術研究部医学系, 助教 (50779486)
• Project Period (FY): 2020-04-01 – 2023-03-31
• Keywords: CTSC / CTC / CD44 / EpCAM

Outline of Final Research Achievements

Six ml of peripheral blood was collected from gastrointestinal cancer patients before and after surgery and chemotherapy, and the mononuclear cell layer was separated using a blood cell separation solution. The cells isolated by flow cytometry using double staining with EpCAM and CD44 were detected as Circulating Tumour Stem Cells (CTSCs) in the peripheral blood, and their counts were measured and analysed in the resected cases. A significant correlation was found between the number of CTSCs detected in 26 gastric cancer cases and wall depth and venous invasion in resected specimens. The study was extended to gastrointestinal cancers, and the changes in CTSCs induced by anti-cancer drugs were evaluated in comparison with the anti-tumour effect in clinical practice, and a decrease in CTSCs was confirmed in patients who had responded to treatment.

Free Research Field

消化器外科

Academic Significance and Societal Importance of the Research Achievements

消化器癌症例の末梢血を6ml採取し、2種類の細胞表面マーカー（CD44とEpCAM）を用いて染色された細胞を検出した。これを末梢血循環癌幹細胞（CTSC）と定義し、この細胞数の変化を担癌患者の治療前後で測定比較した。実際に抗癌剤治療を行った胃癌・膵癌患者においてCTSCの数が減少していることが捕らえられ、よってこのCTSCは治療効果判定のツールとしての利用価値があると考えられる。