Application of methylation rate in acute childhood leukemia to microscopic residual disease analysis.

2022 Fiscal Year Final Research Report

• Project/Area Number: 18K15664
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 52050:Embryonic medicine and pediatrics-related
• Research Institution: University of Yamanashi
• Principal Investigator: Shinohara Tamao 山梨大学, 大学院総合研究部, 医学研究員 (80747452)
• Project Period (FY): 2018-04-01 – 2023-03-31
• Keywords: 小児急性白血病 / 微小残存病変

Outline of Final Research Achievements

Approximately 485 000 CpG sequences were analysed from methylome data in 663 BCP-ALL and 101 T-ALL cases and 86 remission bone marrow cases in the database, and several regions were identified in BCP-ALL and T-ALL cases, respectively, that are highly methylated in leukaemia cells and unmethylated in remission bone marrow. Several regions were identified in leukaemia cells and unmethylated bone marrow in remission. These CpG sites were analysed by next-generation sequencing using cell lines (n = 37) and cryopreserved primary clinical samples (n = 49), and the same regions were also highly methylated in leukaemia cell lines.
The best primer design was planned to be applied to clinical samples, but due to difficulties in primer design, it was difficult to apply the primers to clinic

Free Research Field

小児血液学

Academic Significance and Societal Importance of the Research Achievements

ALLの化学療法において初期治療の反応性をMRDとしてその後の治療に反映させることが国際的なコンセンサスとなっている。しかし、現方法ではMRDの評価が不能な症例が10-20%の割合で存在するため、MRD解析における新たな検査方法の確立が望まれていた。われわれの方法は白血病細胞に特異的なゲノムの異常メチル化が認められる点に注目し、MRDの指標としての可能性について700例を越えるALL症例のメチル化データベースを活用して検討し、その可能性を見出したが臨床検体におけるprimer設計に難渋し応用が困難であった。しかし、MRD解析の方法に関して現行法だけではない可能性を見出したと考える。