Investigation of urinal biomarkers using metabolome technique for prostate cancer radiotherapy

2023 Fiscal Year Final Research Report

• Project/Area Number: 20K16685
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 52040:Radiological sciences-related
• Research Institution: Hirosaki University
• Principal Investigator: Obara Hideki 弘前大学, 医学部附属病院, 放射線技師 (10776610)
• Project Period (FY): 2020-04-01 – 2024-03-31
• Keywords: 前立腺癌 / メタボロミクス / 個別化放射線治療 / 急性期有害事象

Outline of Final Research Achievements

In this study, a retrospective analysis was conducted to predict acute AEs through VMAT for prostate cancer according to urinal metabolomic molecules. Urine samples from a total of 11 patients with prostate cancer who were administered treatment via VMAT (76 Gy/38 fractions) were collected. The findings revealed seven patients with genitourinary toxicity (Grade 1) and four patients with nonAEs. Thereafter, the 630 urinal metabolites were analyzed using a mass spectrometer, and 234 relevant molecules were extracted from the absolute quantified values of metabolites using the MetaboINDICATOR. In the Grade 1 group of acute AEs, a significant negative correlation (r=－0.297, p<0.05) between the number of fractions by VMAT and total phospholipase A2 activity in the urine was noted. Additionally, a decrease in PC aa C40:1 was demonstrated in Grade 1 patients. These results suggest that specific lipids in urinal metabolites have the potential to be predictive biomarkers for acute AEs in VMAT.

Free Research Field

放射線治療

Academic Significance and Societal Importance of the Research Achievements

限局性前立腺癌患者に対する放射線治療は，急性期有害事象を生じることが多く，その後の治療やQOLに影響を及ぼす可能性がある．照射回数と尿中の総ホスホリパーゼA2活性との間に有意な負の相関(r=-0.297，p<0.05)を認め，PC aa C40:1の減少が示された．PC aa C40:1は照射1回目および30回目において急性期有害事象発生に関して，高い特異性と感度を示した．ゆえに，尿中代謝産物中の特異的脂質は，VMATにおける急性期有害事象の予測バイオマーカーとなる可能性が示唆された．個々の患者に合わせた放射線治療を行う一助となる．