title: Radiosensitivity and capacity for radiation-induced sublethal damage repair of canine transitional cell carcinoma (TCC) cell lines.
abstract: Understanding the inherent radiosensitivity and repair capacity of canine transitional cell carcinoma (TCC) can aid in optimizing radiation protocols to treat this disease. The objective of this study was to evaluate the parameters surviving fraction at 2 Gy (SF(2) ), α/β ratio and capacity for sublethal damage repair (SLDR) in response to radiation. Dose-response and split-dose studies were performed using the clonogenic assay. The mean SF(2) for three established TCC cell lines was high at 0.61. All the three cell lines exhibited a low to moderate α/β ratio, with the mean being 3.27. Two cell lines exhibited statistically increased survival at 4 and 24 h in the dose-response assay. Overall, our results indicate that the cell lines are moderately radioresistant, have a high repair capacity and behave similarly to a late-responding normal tissue. These findings indicate that the radiation protocols utilizing higher doses with less fractionation may be more effective for treating TCC.
authors.affiliation: Department of Small Animal Clinical Sciences, College of Veterinary Medicine, University of Florida, Gainesville, FL, USA.
authors.forename: S L
authors.initials: SL
authors.lastname: Parfitt
authors.forename: R J
authors.initials: RJ
authors.lastname: Milner
authors.forename: M E
authors.initials: ME
authors.lastname: Salute
authors.forename: D E
authors.initials: DE
authors.lastname: Hintenlang
authors.forename: J P
authors.initials: JP
authors.lastname: Farese
authors.forename: N J
authors.initials: NJ
authors.lastname: Bacon
authors.forename: F J
authors.initials: FJ
authors.lastname: Bova
authors.forename: D A
authors.initials: DA
authors.lastname: Rajon
authors.forename: D M
authors.initials: DM
authors.lastname: Lurie
mesh_terms: D000818:Animals; D002295:Carcinoma, Transitional Cell / Q000473:pathology / Q000532:radiotherapy / Q000662:veterinary*; D045744:Cell Line, Tumor; D004283:Dog Diseases / Q000473:pathology / Q000532:radiotherapy*; D004285:Dogs; D019583:Dose Fractionation, Radiation; D004307:Dose-Response Relationship, Radiation; D011836:Radiation Tolerance; D014571:Urologic Neoplasms / Q000473:pathology / Q000532:radiotherapy / Q000662:veterinary*