Evaluation of radiotoxicity after iodine-131 therapy using DNA damage in lymphocytes

• Project/Area Number: 24591794
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Radiation science
• Research Institution: Kanazawa Medical University
• Principal Investigator: WATANABE Naoto 金沢医科大学, 医学部, 教授 (40210926)
• Co-Investigator(Kenkyū-buntansha): IWABUCHI Kuniyoshi 金沢医科大学, 医学部, 教授 (10232696) ; DOAI Mariko 金沢医科大学, 医学部, 助教 (40515673)
• Project Period (FY): 2012-04-01 – 2016-03-31
• Project Status: Completed (Fiscal Year 2015)
• Budget Amount: ¥5,330,000 (Direct Cost: ¥4,100,000、Indirect Cost: ¥1,230,000); Fiscal Year 2015: ¥1,170,000 (Direct Cost: ¥900,000、Indirect Cost: ¥270,000); Fiscal Year 2014: ¥1,170,000 (Direct Cost: ¥900,000、Indirect Cost: ¥270,000); Fiscal Year 2013: ¥1,170,000 (Direct Cost: ¥900,000、Indirect Cost: ¥270,000); Fiscal Year 2012: ¥1,820,000 (Direct Cost: ¥1,400,000、Indirect Cost: ¥420,000)
• Keywords: 甲状腺癌 / 放射線障害 / リンパ球 / γ-H2AX / 放射線組織障害 / DNA損傷 / 放射性ヨード治療

Outline of Final Research Achievements

The purpose of our study was to evaluate the degree of cytological radiation damage to lymphocytes after I-131 therapy using γ-H2AX foci immunodetection. Methods: This study focused on 15 patients who underwent I-131 therapy. Venous blood samples were collected from each patient before therapy and 4 days thereafter. Lymphocytes were isolated and subjected to γ-H2AX immunofluorescence staining. Results: The number of foci per lymphocyte nucleus was 0.41 ± 0.51 before and 6.19 ± 1.80 after radioiodine therapy, and this difference was statistically significant. Absorbed doses estimated were 0.77± 0.31Gy. Conclusion: Our study suggests that γ-H2AX foci immunodetection is useful as a biomarker for the evaluation of the radiotoxicity after I-131 therapy. γ-H2AX foci immunodetection in lymphocytes may detect radiation-induced DNA damage associated with I-131 therapy of thyroid cancer.

Research Products

• [Journal Article] 甲状腺癌のヨード治療におけるリンパ球の放射線障害について (2015)
  • Author(s): 渡邉直人
  • Journal Title: 金沢医科大学雑誌 Volume: ４０ Pages: 182-185
  • Peer Reviewed / Acknowledgement Compliant
• [Presentation] Radiation-induced damage in lymphocytes after radioisotope therapy for bone metastases. (2015)
  • Author(s): 渡邉直人
  • Organizer: 第74回日本医学放射線学会総会
  • Place of Presentation: パシフィコ横浜(神奈川県横浜市）
  • Year and Date: 2015-04-16
• [Presentation] 除痛目的のアイソトープ治療におけるリンパ球の放射線組織障害評価に関する検討 (2014)
  • Author(s): 道合万里子
  • Organizer: 第５５回日本核医学会総会
  • Place of Presentation: 大阪国際会議場(大阪府大阪市）
  • Year and Date: 2014-11-06 – 2014-11-08
• [Presentation] 除痛目的のアイソトープ治療におけるリンパ球の放射線組織障害に関する検討 (2013)
  • Author(s): 道合万里子
  • Organizer: 第５３回日本核医学会総会
  • Place of Presentation: 福岡国際会議場（ 福岡県福岡市 ）
• [Presentation] アイソトープ治療におけるリンパ球の放射線組織障害評価に関する検討(第二報） (2012)
  • Author(s): 道合万里子
  • Organizer: 第52回日本核医学会総会
  • Place of Presentation: ロイトン札幌