Elucidation of Breast Cancer Endocrine Therapy Resistance by Single Cell Analysis using Blood Circulating Tumor Cells

2020 Fiscal Year Final Research Report

• Project/Area Number: 18K08572
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 55010:General surgery and pediatric surgery-related
• Research Institution: Yamaguchi University
• Principal Investigator: Yamamoto Shigeru 山口大学, 医学部, 特別医学研究員 (30289178)
• Co-Investigator(Kenkyū-buntansha): 前田 訓子 山口大学, 医学部附属病院, 助教 (10738876) ; 水上 洋一 山口大学, 大学研究推進機構, 教授 (80274158) ; 佐藤 陽子 山口大学, 医学部附属病院, 診療助教(4日/週) (70794676)
• Project Period (FY): 2018-04-01 – 2021-03-31
• Keywords: CTC / 乳癌 / RNA-seq / シングルセル

Outline of Final Research Achievements

We investigated single-cell next-generation sequencing technology and found that the Quartz-seq method enabled us to analyze the expression of 8000 genes from a single cell. Therefore, we performed single-cell RNA-seq analysis of CTCs isolated by the sorter, but only about 100 genes were detected, and RNA degradation was accelerated by using the cell sorter. Therefore, the laser setting was changed and only viable cells were isolated and purified from cells isolated from postoperative breast cancer tissues using a cell sorter with less damage to the cells. As a result, around 8,000 genes were detected from a single cell, allowing for detailed analysis of leukocyte contamination.

Free Research Field

乳腺外科

Academic Significance and Societal Importance of the Research Achievements

エストロゲンレセプター(ERα)陽性/HER-2陰性の転移・再発乳癌は、内分泌療法に対しほとんどの症例で治療抵抗性を獲得しており、新たな治療法の開発は喫緊の課題である。原発巣から血流に流入した乳癌細胞は、転移再発までの抵抗性獲得時点でのリアルタイムスナップショットとみなすことができる。このため再発患者の血中循環腫瘍細胞（CTC）の全遺伝子を網羅的に解析し、初回手術時の原発巣の変異と比較検討し遺伝子変動を正確に把握することが最も重要である。