Investigation of plasma membrane repair in X-ray and C-ion resistant cancer cells

2016 Fiscal Year Final Research Report

• Project/Area Number: 15K15467
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Radiation science
• Research Institution: Japanese Foundation for Cancer Research (2016); National Institute of Radiological Sciences (2015)
• Principal Investigator: Katsutoshi Sato 公益財団法人がん研究会, 有明病院 遺伝子診療部, 研究員 (20589650)
• Project Period (FY): 2015-04-01 – 2017-03-31
• Keywords: 粒子線治療 / 炭素イオン線抵抗性がん細胞株 / 細胞膜修復

Outline of Final Research Achievements

X-ray and carbon ion beam (C-ion) resistant cancer cell X60 abundantly contained lysosomes, ATP, mitochondria, and reactive oxygen species. In addition, mTOR signaling, which is associated with regulation of energy production, was promoted in X60 cells. Inhibition of the mTOR signaling significantly decreased the X-ray and C-ion resistance in X60 cells. Therefore our results showed that mTOR signaling contributes the X-ray and C-ion resistance in cancer cells. Futhermore, the X60 cells were significantly resistant to plasma membrane damage which is induced by Streptolysin O treatment. Our results indicated that the X60 cells have a lot of Flottilin-1 domain on plasma membrane, which closely associated with lipid raft formation and endocytosis. Given these results, regulation of plasma membrane including lipid raft formation and endocytosis might also contribute to X-ray and C-ion resistance in cancer cells.

Free Research Field

医歯薬学