Stereotactic body radiotherapy for oral cancer: Mechanism of efficient tumor cell killing from cell cycle kinetics

2017 Fiscal Year Final Research Report

• Project/Area Number: 16K15784
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Pathobiological dentistry/Dental radiology
• Research Institution: Tokyo Medical and Dental University
• Principal Investigator: MIURA Masahiko 東京医科歯科大学, 大学院医歯学総合研究科, 教授 (10272600)
• Project Period (FY): 2016-04-01 – 2018-03-31
• Keywords: 定位照射 / 細胞周期動態 / 口腔がん

Outline of Final Research Achievements

Stereotactic body radiotherapy (SBRT) is recently established as an excellent modality for Stage I non-small lung cancer and is also applied for oral cancer. Its fractionation is very unique in that dose per fraction is large (~12 Gy) and fraction number is only several times. However, radiobiological analysis has rarely been performed thus far. The aim of this study was to study the mechanism underlying the excellent clinical results of SBRT from the viewpoint of cell cycle kinetics utilizing Fucci, a cell cycle visualizing system. It was revealed that irradiation of 10 Gy per fraction remarkably enhanced the ratio of cells synchronized at the G2/M checkpoint compared to that of 5 x 2 Gy per fraction. Considering that cells at G2/M boundary are radiosensitive, the observed cell cycle kinetics could be a reason of the outstanding clinical results by SBRT.

Free Research Field

病態科学系歯学・歯科放射線学