Suicide gene therapy for malignant glioma using genome-edited human induced pluripotent stem cells

2021 Fiscal Year Final Research Report

• Project/Area Number: 19K16872
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 50020:Tumor diagnostics and therapeutics-related
• Research Institution: Keio University
• Principal Investigator: MURASE Makoto 慶應義塾大学, 医学部(信濃町), 助教 (30836755)
• Project Period (FY): 2019-04-01 – 2022-03-31
• Keywords: 悪性神経膠腫 / 自殺遺伝子 / iPS細胞 / 神経幹細胞 / CRISPR/Cas9

Outline of Final Research Achievements

We demonstrated that human induced pluripotent stem cells (iPSCs)-derived neural stem cells (NSCs) possess the higher tumor-tropic migratory capacity than mesenchymal stem cells. Therefore, we established the concept of suicide gene therapy using iPSCs-derived NSCs as a cellular delivery vehicle for the treatment of malignant glioma. Lentiviral vectors integrated randomly into the host genome, raising concerns about insertional mutagenesis, oncogene activation, and transgene silencing. In order to improve safety and to achieve stable transgene expression, yCD-UPRT was inserted into a housekeeping gene locus in iPSCs using CRISPR/Cas9-mediated genome editing, resulting in a significantly better anti-tumor effect for human glioma and glioma stem xenograft mice than temozolomide (standard chemotherapy). In addition, time-lapse imaging of organotypic brain slice cultures could quantitatively visualize the migration of NSCs and bystander killing of glioma cells and glioma stem cells.

Free Research Field

脳神経外科学

Academic Significance and Societal Importance of the Research Achievements

樹立した抗腫瘍効果を生む治療用NSCは、5-FCの投与により死滅するため、安全性は高く、その効果が細胞周期依存性であることから、終末分化した神経細胞などからなる正常脳組織には影響しない。また、当然その他の難治性脳腫瘍への応用も可能であり、iPS細胞を再生医療以外の疾患(がん)治療に応用した1st clinical trial modelとなり得る。さらに、本システムはiPS細胞を用いた再生医療において、造腫瘍性の問題を解消する安全装置としても利用できるため、iPS細胞を様々な遺伝子細胞治療に応用するためのプラットフォームにもなる。