Development of the loco-systemic cancer therapy combining localized radiation and novel immune adjuvant mesoporous silica

2015 Fiscal Year Final Research Report

• Project/Area Number: 26670548
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Radiation science
• Research Institution: University of Tsukuba
• Principal Investigator: Tsuboi Koji 筑波大学, 医学医療系, 教授 (90188615)
• Co-Investigator(Kenkyū-buntansha): ZENKOH Junko 筑波大学, 医学医療系, 研究員 (20710148) ; ITO Atsuo 国立研究開発法人産業技術総合研究所, 生命工学領域 健康工学研究部門 生体材料研究グループ, 研究グループ長 (30356480)
• Project Period (FY): 2014-04-01 – 2016-03-31
• Keywords: 放射線治療生物学 / 免疫応答細胞死

Outline of Final Research Achievements

Localized radiotherapy for cancers has an effect of immune adjuvant by inducing immunogenic cell death. The signals from dying or newly dead cells evoke anti-tumor immunity that is mediated by activated CTLs.
In this study, murine glioma cells GL261 were inoculated to syngeneic albino C57BL/6 mice. Mesoporous silica nanoparticles (MSNs) were used as an immune adjuvant. Intra-tumoral injection of MSNs was combined with localized X-ray irradiation, and the tumor growth rates and survival were analyzed. In addition, the immune-enhancing effect of indomethacin was examined.
Consequently, MSNs administration (0.1 mg/mouse) once a week for 3 weeks delayed tumor growth significantly. Moreover, 6 times administrations induced complete cure in 90% of the treated mice inducing abscopal effect in the brain. Furthermore, sequential oral administration of indomethacin enhanced anti-tumor effect and prolonged survivals of the mice. MSNs may be a promising candidate for a novel immune adjuvant.

Free Research Field

放射線生物学・放射線腫瘍学