Establishment of a Novel Liquid Biopsy Technique for Colorectal Cancer Using MicroRNA Editing in Blood

2021 Fiscal Year Final Research Report

• Project/Area Number: 20K22848
• Research Category: Grant-in-Aid for Research Activity Start-up
• Allocation Type: Multi-year Fund
• Review Section: 0901:Oncology and related fields
• Research Institution: Okayama University
• Principal Investigator: Takeda Sho 岡山大学, 大学病院, 医員 (20872980)
• Project Period (FY): 2020-09-11 – 2022-03-31
• Keywords: RNA編集 / 大腸癌 / PCR / 上皮間葉形質転換

Outline of Final Research Achievements

Since cancer cells change their properties during the course of treatment, there is no assurance that the information from the primary tumor is the same in the metastases as it is in the metastases. Based on the results of our previous RNA editing analysis, we thought that the concept of liquid biopsy could be applied not only to DNA but also to RNA editing. However, RNA editing analysis using next-generation sequencers is expensive and requires a large amount of RNA to be analyzed, making it impossible to detect the small amount of edited miRNAs derived from tumors in blood.
We were able to overcome this technical challenge by developing a novel TaqmanPCR primer. It is now possible to detect RNA editing of microRNAs in tumor cells even from minute amounts of RNA.

Free Research Field

大腸癌のエピジェネティクス

Academic Significance and Societal Importance of the Research Achievements

消化器癌では、RNA編集酵素のAdenosine deaminase acting on RNA 1 (ADAR1)の発現が上昇し、標的となるRNAの塩基置換が促進されることで、癌の悪性度が増す。RNA編集は主にlong RNAにつき解析されてきたが、近年、癌におけるマイクロRNA編集の上昇が注目され始めた。マイクロRNAは血液中でも安定して存在しており、リキッドバイオプシーの対象として最適である。我々は、血液中で安定して存在するマイクロRNAのRNA編集の解析をTaqmanPCRで行う方法を完成させた。大腸癌患者の血液におけるmiRNA editingを実際に解析できるようになった。