title: Local tumor control and DNA-PK activity of peripheral blood lymphocytes in prostate cancer patients receiving radiotherapy.
abstract: Repair of DNA damage is critical for genomic stability, and DNA-dependent protein kinase (DNA-PK) has an important role in repairing double-strand breaks. We examined whether the DNA-PK activity of peripheral blood lymphocytes (PBLs) was related to biochemical (prostate-specific antigen: PSA) relapse and radiation toxicity in prostate cancer patients who have received radiotherapy. A total of 69 patients with localized adenocarcinoma of the prostate participated in this study. Peripheral blood was collected 2 years or later after radiotherapy and centrifuged, then DNA-PK activity was measured by a filter binding assay. The high DNA-PK activity group had a significantly higher PSA relapse-free survival rate than the low DNA-PK activity group. The 10-year PSA relapse-free survival was 87.0% in the high DNA-PK activity group, whereas it was 52.7% in the low DNA-PK activity group. Multivariate analysis showed the Gleason score and the level of DNA-PK activity were significant predictors of PSA relapse after radiotherapy. In addition, the low DNA-PK activity group tended to have a higher incidence of Grade 1-2 urinary toxicity than the high DNA-PK activity group. Prostate cancer patients with low DNA-PK activity had a higher rate of PSA relapse and a higher incidence of urinary toxicity. DNA-PK activity in PBLs might be a useful marker for predicting PSA relapse and urinary toxicity, possibly contributing to personalized treatment of prostate cancer.
authors.affiliation: Department of Radiology, Sapporo Medical University School of Medicine, S1W16, Chuo-ku, Sapporo, Hokkaido, 060-8543, Japan.
authors.forename: Masanori
authors.initials: M
authors.lastname: Someya
authors.affiliation: Department of Radiology, Sapporo Medical University School of Medicine, S1W16, Chuo-ku, Sapporo, Hokkaido, 060-8543, Japan.
authors.forename: Tomokazu
authors.initials: T
authors.lastname: Hasegawa
authors.affiliation: Department of Radiology, Sapporo Medical University School of Medicine, S1W16, Chuo-ku, Sapporo, Hokkaido, 060-8543, Japan.
authors.forename: Masakazu
authors.initials: M
authors.lastname: Hori
authors.affiliation: Research Laboratory for Nuclear Reactors, Tokyo Institute of Technology, Tokyo, Japan.
authors.forename: Yoshihisa
authors.initials: Y
authors.lastname: Matsumoto
authors.affiliation: Department of Radiology, Sapporo Medical University School of Medicine, S1W16, Chuo-ku, Sapporo, Hokkaido, 060-8543, Japan.
authors.forename: Kensei
authors.initials: K
authors.lastname: Nakata
authors.affiliation: Department of Urology, Sapporo Medical University School of Medicine, S1W16, Chuo-ku, Sapporo, Hokkaido, 060-8543, Japan.
authors.forename: Naoya
authors.initials: N
authors.lastname: Masumori
authors.affiliation: Department of Radiology, Sapporo Medical University School of Medicine, S1W16, Chuo-ku, Sapporo, Hokkaido, 060-8543, Japan.
authors.forename: Koh-Ichi
authors.initials: KI
authors.lastname: Sakata
mesh_terms: D000368:Aged; D051747:DNA-Activated Protein Kinase / Q000097:blood*; D006801:Humans; D007963:Leukocytes, Mononuclear / Q000201:enzymology*; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D017430:Prostate-Specific Antigen / Q000097:blood; D011471:Prostatic Neoplasms / Q000097:blood / Q000201:enzymology* / Q000532:radiotherapy* / Q000652:urine; D012008:Recurrence; D012307:Risk Factors
chemical_list: D051747:DNA-Activated Protein Kinase; D017430:Prostate-Specific Antigen
keywords: DNA-PK activity; late urinary toxicity; predictive assay; prostate cancer; radiotherapy