Pooled shRNA screening for novel potential drug targets in T-ALL

2018 Fiscal Year Final Research Report

• Project/Area Number: 16K09840
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Hematology
• Research Institution: Shimane University (2018); Chiba University (2016-2017)
• Principal Investigator: Miyagi Satoru 島根大学, 学術研究院医学・看護学系, 准教授 (20400997)
• Project Period (FY): 2016-04-01 – 2019-03-31
• Keywords: T細胞性急性リンパ性白血病 / クロマチンタンパク質 / shRNA スクリーン / 創薬標的

Outline of Final Research Achievements

Acute lymphoblastic leukemia (ALL) is a disease with poor survival, therefore, development of molecular target drugs is awaited to improve the prognosis of ALL patients.
In this study, I used a short hairpin RNA (shRNA) library against chromatin modifiers, which play a pivotal role in normal hematopoiesis and leukemogenesis, to screen for novel potential drug targets in T-cell acute lymphoblastic leukemia (T-ALL). As a counter-screen for general toxicity of shRNAs, we used normal human fibroblast cells. One of the best candidate drug targets identified in these screens was METTL18, which is supporsed to be an uncharacterized methyl-transferase. Depletion of METTL18 impairs growth of human T-ALL cell lines, but not normal cell, in vitro in dose-dependent manner and we observed the correlation between the expression level of METTL18 and cell growth rate in T-ALL lines, indicating METTL18 is an important regulator of T-ALL cells growth and is an ideal drug-target in T-ALL.

Free Research Field

血液学

Academic Significance and Societal Importance of the Research Achievements

急性リンパ性白血病は予後不良の白血病であり、長期生存率が20-40%と低く、細胞障害性の少ない分子標的薬の開発が急務である。本研究では、RNAiスクリーニングを行い、T細胞性急性リンパ性白血病(T-ALL)細胞の増殖に必須の遺伝子群(METTL18、SHPRH、HDAC6)を同定した。METTL18は、基質が同定されいないものの、その構造からメチル化酵素であると想定されており、この酵素活性を指標とした低分子阻害剤の開発が可能である。従って、METTL18はT-ALLに対する分子標的薬の開発シーズとなる。