Prognostic prediction of radiotherapy (The relativeness of radioresistance and cancer invation , matastasis)

• Project/Area Number: 17K10485
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Radiation science
• Research Institution: Kagoshima University
• Principal Investigator: INDO HIROKO 鹿児島大学, 医歯学域歯学系, 准教授 (00301391)
• Co-Investigator(Kenkyū-buntansha): 末永 重明 鹿児島大学, 医歯学域鹿児島大学病院, 講師 (00136889) ; 長澤 大成 鹿児島大学, 医歯学域歯学系, 助教 (50773925) ; 馬嶋 秀行 鹿児島大学, 医歯学域歯学系, 教授 (60165701) ; 伊藤 紘 鹿児島大学, 医歯学域歯学系, 助教 (80793934)
• Project Period (FY): 2017-04-01 – 2020-03-31
• Project Status: Completed (Fiscal Year 2019)
• Budget Amount: ¥4,160,000 (Direct Cost: ¥3,200,000、Indirect Cost: ¥960,000); Fiscal Year 2019: ¥1,560,000 (Direct Cost: ¥1,200,000、Indirect Cost: ¥360,000); Fiscal Year 2018: ¥1,170,000 (Direct Cost: ¥900,000、Indirect Cost: ¥270,000); Fiscal Year 2017: ¥1,430,000 (Direct Cost: ¥1,100,000、Indirect Cost: ¥330,000)
• Keywords: 放射線抵抗性 / 癌 / 転移 / 放射線

Outline of Final Research Achievements

A rat squamous cell carcinoma cell line SCC-158, of which p53 status is wild, was used in this study. Spheroids, of which diameter is (150 ,300,450) um were subjected to X-irradiation at the dose of 500mGy/day for 10, 20 and 30 days (10 days, 20 days and 30 days Groups). The survived cells were recovered and subjected to examine its characteristic cancer invasion and metastasis. Among the culture day group, the 10 days group showed the highest expressions of p53 and S100A4 that is related to metastasis, and also showed highest amount of p53 phosphorylation. These results may suggest that radio-resistance may be acquired during the irradiation process, leading to cancer invasion and metastasis.

Academic Significance and Societal Importance of the Research Achievements

スフェロイドを作成し、腫瘍塊にX線照射を行うので、通常の2次元培養細胞よりも臨床に近い状態にて実験を遂行することができる。癌の放射線治療を行う上で、放射線抵抗性の獲得と癌の転移との関連性について明らかにすることは放射線治療が有効であるかどうか、また再発・後発転移するかどうかの予後の判定が可能になることが予測される。また放射線抵抗性の獲得の機序解明へとつながることも予想され、放射線治療研究分野への大いなる貢献が期待される。

Research Products

• [Presentation] Effects of Extremely Small Doses, 100 mGy a Day, Five Times a Week, Total of Twelve Weeks of Low-Dose Fractionated X-irradiation on Mice Hair (2019)
  • Author(s): Hideyuki J. Majima, Hiromu Ito, Tomoko Fukushige, Hiroko P. Indo, Yoshihiro Kawabata, Ken-ichiro Matsumoto, Ikuo Nakanishi, Akihide Tanimoto, Takuro Kanekura, Clare L. Hawkins, Michael J. Davies, William St. Clair and Daret K St Clair
  • Organizer: 26th Annual Meeting of the Society for Redox Biology & Medicine
  • Int'l Joint Research